1 | // SigmaExtraDim.cc is a part of the PYTHIA event generator. |
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2 | // Copyright (C) 2012 Torbjorn Sjostrand. |
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3 | // Copyright (C) 2012 Stefan Ask for the *LED* routines. |
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4 | // PYTHIA is licenced under the GNU GPL version 2, see COPYING for details. |
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5 | // Please respect the MCnet Guidelines, see GUIDELINES for details. |
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6 | |
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7 | // Function definitions (not found in the header) for the |
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8 | // extra-dimensional simulation classes. |
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9 | |
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10 | #include "SigmaExtraDim.h" |
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11 | |
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12 | namespace Pythia8 { |
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13 | |
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14 | //========================================================================== |
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15 | |
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16 | // ampLedS (amplitude) method for LED graviton tree level exchange. |
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17 | // Based on Eq. (8) in JHEP 1105 (2011) 092, arXiv:1101.4919. |
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18 | |
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19 | complex ampLedS(double x, double n, double L, double M) { |
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20 | |
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21 | complex cS(0., 0.); |
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22 | if (n <= 0) return cS; |
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23 | |
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24 | // Constants. |
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25 | double exp1 = n - 2; |
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26 | double exp2 = n + 2; |
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27 | double rC = sqrt(pow(M_PI,n)) * pow(L,exp1) |
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28 | / (GammaReal(n/2.) * pow(M,exp2)); |
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29 | |
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30 | // Base functions, F1 and F2. |
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31 | complex I(0., 1.); |
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32 | if (x < 0) { |
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33 | double sqrX = sqrt(-x); |
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34 | if (int(n) % 2 == 0) { |
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35 | cS = -log(fabs(1 - 1/x)); |
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36 | } else { |
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37 | cS = (2.*atan(sqrX) - M_PI)/sqrX; |
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38 | } |
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39 | } else if ((x > 0) && (x < 1)) { |
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40 | double sqrX = sqrt(x); |
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41 | if (int(n) % 2 == 0) { |
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42 | cS = -log(fabs(1 - 1/x)) - M_PI*I; |
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43 | } else { |
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44 | double rat = (sqrX + 1)/(sqrX - 1); |
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45 | cS = log(fabs(rat))/sqrX - M_PI*I/sqrX; |
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46 | } |
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47 | } else if (x > 1){ |
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48 | double sqrX = sqrt(x); |
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49 | if (int(n) % 2 == 0) { |
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50 | cS = -log(fabs(1 - 1/x)); |
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51 | } else { |
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52 | double rat = (sqrX + 1)/(sqrX - 1); |
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53 | cS = log(fabs(rat))/sqrX; |
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54 | } |
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55 | } |
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56 | |
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57 | // Recursive part. |
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58 | int nL; |
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59 | int nD; |
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60 | if (int(n) % 2 == 0) { |
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61 | nL = int(n/2.); |
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62 | nD = 2; |
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63 | } else { |
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64 | nL = int((n + 1)/2.); |
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65 | nD = 1; |
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66 | } |
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67 | for (int i=1; i<nL; ++i) { |
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68 | cS = x*cS - 2./nD; |
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69 | nD += 2; |
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70 | } |
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71 | |
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72 | return rC*cS; |
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73 | } |
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74 | |
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75 | //-------------------------------------------------------------------------- |
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76 | |
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77 | // Common method, "Mandelstam polynomial", for LED dijet processes. |
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78 | |
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79 | double funLedG(double x, double y) { |
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80 | double ret = pow(x,4) + 10. * pow(x,3) * y + 42. * pow2(x) * pow2(y) |
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81 | + 64. * x * pow(y,3) + 32. * pow(y,4); |
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82 | return ret; |
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83 | } |
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84 | |
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85 | //========================================================================== |
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86 | |
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87 | // Sigma1gg2GravitonStar class. |
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88 | // Cross section for g g -> G* (excited graviton state). |
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89 | |
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90 | //-------------------------------------------------------------------------- |
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91 | |
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92 | // Initialize process. |
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93 | |
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94 | void Sigma1gg2GravitonStar::initProc() { |
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95 | |
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96 | // Store G* mass and width for propagator. |
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97 | idGstar = 5100039; |
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98 | mRes = particleDataPtr->m0(idGstar); |
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99 | GammaRes = particleDataPtr->mWidth(idGstar); |
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100 | m2Res = mRes*mRes; |
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101 | GamMRat = GammaRes / mRes; |
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102 | |
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103 | // SMinBulk = off/on, use universal coupling (kappaMG) |
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104 | // or individual (Gxx) between graviton and SM particles. |
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105 | eDsmbulk = settingsPtr->flag("ExtraDimensionsG*:SMinBulk"); |
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106 | eDvlvl = false; |
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107 | if (eDsmbulk) eDvlvl = settingsPtr->flag("ExtraDimensionsG*:VLVL"); |
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108 | kappaMG = settingsPtr->parm("ExtraDimensionsG*:kappaMG"); |
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109 | for (int i = 0; i < 27; ++i) eDcoupling[i] = 0.; |
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110 | double tmPcoup = settingsPtr->parm("ExtraDimensionsG*:Gqq"); |
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111 | for (int i = 1; i <= 4; ++i) eDcoupling[i] = tmPcoup; |
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112 | eDcoupling[5] = settingsPtr->parm("ExtraDimensionsG*:Gbb"); |
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113 | eDcoupling[6] = settingsPtr->parm("ExtraDimensionsG*:Gtt"); |
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114 | tmPcoup = settingsPtr->parm("ExtraDimensionsG*:Gll"); |
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115 | for (int i = 11; i <= 16; ++i) eDcoupling[i] = tmPcoup; |
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116 | eDcoupling[21] = settingsPtr->parm("ExtraDimensionsG*:Ggg"); |
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117 | eDcoupling[22] = settingsPtr->parm("ExtraDimensionsG*:Ggmgm"); |
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118 | eDcoupling[23] = settingsPtr->parm("ExtraDimensionsG*:GZZ"); |
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119 | eDcoupling[24] = settingsPtr->parm("ExtraDimensionsG*:GWW"); |
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120 | eDcoupling[25] = settingsPtr->parm("ExtraDimensionsG*:Ghh"); |
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121 | |
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122 | // Set pointer to particle properties and decay table. |
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123 | gStarPtr = particleDataPtr->particleDataEntryPtr(idGstar); |
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124 | |
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125 | } |
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126 | |
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127 | //-------------------------------------------------------------------------- |
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128 | |
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129 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
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130 | |
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131 | void Sigma1gg2GravitonStar::sigmaKin() { |
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132 | |
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133 | // Incoming width for gluons. |
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134 | double widthIn = mH / (160. * M_PI); |
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135 | |
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136 | // RS graviton coupling |
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137 | if (eDsmbulk) widthIn *= 2. * pow2(eDcoupling[21] * mH); |
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138 | else widthIn *= pow2(kappaMG); |
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139 | |
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140 | // Set up Breit-Wigner. Width out only includes open channels. |
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141 | double sigBW = 5. * M_PI/ ( pow2(sH - m2Res) + pow2(sH * GamMRat) ); |
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142 | double widthOut = gStarPtr->resWidthOpen(idGstar, mH); |
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143 | |
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144 | // Modify cross section in wings of peak. Done. |
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145 | sigma = widthIn * sigBW * widthOut * pow2(sH / m2Res); |
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146 | |
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147 | } |
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148 | |
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149 | //-------------------------------------------------------------------------- |
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150 | |
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151 | // Select identity, colour and anticolour. |
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152 | |
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153 | void Sigma1gg2GravitonStar::setIdColAcol() { |
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154 | |
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155 | // Flavours trivial. |
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156 | setId( 21, 21, idGstar); |
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157 | |
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158 | // Colour flow topology. |
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159 | setColAcol( 1, 2, 2, 1, 0, 0); |
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160 | |
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161 | } |
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162 | |
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163 | //-------------------------------------------------------------------------- |
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164 | |
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165 | // Evaluate weight for G* decay angle. |
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166 | // SA: Angle dist. for decay G* -> W/Z/h, based on |
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167 | // Phys.Rev. D65 (2002) 075008, [arXiv:hep-ph/0103308v3] |
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168 | |
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169 | double Sigma1gg2GravitonStar::weightDecay( Event& process, int iResBeg, |
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170 | int iResEnd) { |
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171 | |
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172 | // Identity of mother of decaying reseonance(s). |
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173 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
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174 | |
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175 | // For top decay hand over to standard routine. |
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176 | if (idMother == 6) |
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177 | return weightTopDecay( process, iResBeg, iResEnd); |
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178 | |
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179 | // G* should sit in entry 5. |
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180 | if (iResBeg != 5 || iResEnd != 5) return 1.; |
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181 | |
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182 | // Phase space factors. Reconstruct decay angle. |
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183 | double mr1 = pow2(process[6].m()) / sH; |
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184 | double mr2 = pow2(process[7].m()) / sH; |
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185 | double betaf = sqrtpos( pow2(1. - mr1 - mr2) - 4. * mr1 * mr2); |
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186 | double cosThe = (process[3].p() - process[4].p()) |
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187 | * (process[7].p() - process[6].p()) / (sH * betaf); |
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188 | |
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189 | // Default is isotropic decay. |
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190 | double wt = 1.; |
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191 | |
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192 | // Angular weight for g + g -> G* -> f + fbar. |
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193 | if (process[6].idAbs() < 19) { |
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194 | wt = 1. - pow4(cosThe); |
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195 | |
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196 | // Angular weight for g + g -> G* -> g + g or gamma + gamma. |
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197 | } else if (process[6].id() == 21 || process[6].id() == 22) { |
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198 | wt = (1. + 6. * pow2(cosThe) + pow4(cosThe)) / 8.; |
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199 | |
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200 | // Angular weight for g + g -> G* -> Z + Z or W + W. |
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201 | } else if (process[6].id() == 23 || process[6].id() == 24) { |
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202 | double beta2 = pow2(betaf); |
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203 | double cost2 = pow2(cosThe); |
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204 | double cost4 = pow2(cost2); |
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205 | wt = pow2(beta2 - 2.)*(1. - 2.*cost2 + cost4); |
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206 | // Longitudinal W/Z only. |
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207 | if(eDvlvl) { |
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208 | wt /= 4.; |
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209 | // Transverse W/Z contributions as well. |
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210 | } else { |
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211 | double beta4 = pow2(beta2); |
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212 | double beta8 = pow2(beta4); |
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213 | wt += 2.*pow2(beta4 - 1.)*beta4*cost4; |
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214 | wt += 2.*pow2(beta2 - 1.)*(1. - 2.*beta4*cost2 + beta8*cost4); |
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215 | wt += 2.*(1. + 6.*beta4*cost2 + beta8*cost4); |
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216 | wt += 8.*(1. - beta2)*(1. - cost4); |
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217 | wt /= 18.; |
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218 | } |
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219 | |
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220 | // Angular weight for g + g -> G* -> h + h |
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221 | } else if (process[6].id() == 25) { |
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222 | double beta2 = pow2(betaf); |
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223 | double cost2 = pow2(cosThe); |
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224 | double cost4 = pow2(cost2); |
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225 | wt = pow2(beta2 - 2.)*(1. - 2.*cost2 + cost4); |
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226 | wt /= 4.; |
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227 | } |
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228 | |
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229 | // Done. |
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230 | return wt; |
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231 | |
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232 | } |
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233 | |
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234 | //========================================================================== |
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235 | |
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236 | // Sigma1ffbar2GravitonStar class. |
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237 | // Cross section for f fbar -> G* (excited graviton state). |
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238 | |
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239 | //-------------------------------------------------------------------------- |
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240 | |
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241 | // Initialize process. |
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242 | |
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243 | void Sigma1ffbar2GravitonStar::initProc() { |
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244 | |
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245 | // Store G* mass and width for propagator. |
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246 | idGstar = 5100039; |
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247 | mRes = particleDataPtr->m0(idGstar); |
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248 | GammaRes = particleDataPtr->mWidth(idGstar); |
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249 | m2Res = mRes*mRes; |
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250 | GamMRat = GammaRes / mRes; |
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251 | |
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252 | // SMinBulk = off/on, use universal coupling (kappaMG) |
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253 | // or individual (Gxx) between graviton and SM particles. |
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254 | eDsmbulk = settingsPtr->flag("ExtraDimensionsG*:SMinBulk"); |
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255 | eDvlvl = false; |
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256 | if (eDsmbulk) eDvlvl = settingsPtr->flag("ExtraDimensionsG*:VLVL"); |
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257 | kappaMG = settingsPtr->parm("ExtraDimensionsG*:kappaMG"); |
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258 | for (int i = 0; i < 27; ++i) eDcoupling[i] = 0.; |
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259 | double tmPcoup = settingsPtr->parm("ExtraDimensionsG*:Gqq"); |
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260 | for (int i = 1; i <= 4; ++i) eDcoupling[i] = tmPcoup; |
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261 | eDcoupling[5] = settingsPtr->parm("ExtraDimensionsG*:Gbb"); |
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262 | eDcoupling[6] = settingsPtr->parm("ExtraDimensionsG*:Gtt"); |
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263 | tmPcoup = settingsPtr->parm("ExtraDimensionsG*:Gll"); |
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264 | for (int i = 11; i <= 16; ++i) eDcoupling[i] = tmPcoup; |
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265 | eDcoupling[21] = settingsPtr->parm("ExtraDimensionsG*:Ggg"); |
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266 | eDcoupling[22] = settingsPtr->parm("ExtraDimensionsG*:Ggmgm"); |
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267 | eDcoupling[23] = settingsPtr->parm("ExtraDimensionsG*:GZZ"); |
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268 | eDcoupling[24] = settingsPtr->parm("ExtraDimensionsG*:GWW"); |
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269 | eDcoupling[25] = settingsPtr->parm("ExtraDimensionsG*:Ghh"); |
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270 | |
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271 | // Set pointer to particle properties and decay table. |
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272 | gStarPtr = particleDataPtr->particleDataEntryPtr(idGstar); |
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273 | |
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274 | } |
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275 | |
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276 | //-------------------------------------------------------------------------- |
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277 | |
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278 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
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279 | |
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280 | void Sigma1ffbar2GravitonStar::sigmaKin() { |
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281 | |
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282 | // Incoming width for fermions, disregarding colour factor. |
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283 | double widthIn = mH / (80. * M_PI); |
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284 | |
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285 | // Set up Breit-Wigner. Width out only includes open channels. |
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286 | double sigBW = 5. * M_PI/ ( pow2(sH - m2Res) + pow2(sH * GamMRat) ); |
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287 | double widthOut = gStarPtr->resWidthOpen(idGstar, mH); |
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288 | |
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289 | // Modify cross section in wings of peak. Done. |
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290 | sigma0 = widthIn * sigBW * widthOut * pow2(sH / m2Res); |
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291 | |
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292 | } |
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293 | |
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294 | //-------------------------------------------------------------------------- |
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295 | |
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296 | // Evaluate sigmaHat(sHat), part dependent of incoming flavour. |
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297 | |
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298 | double Sigma1ffbar2GravitonStar::sigmaHat() { |
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299 | |
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300 | double sigma = sigma0; |
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301 | |
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302 | // RS graviton coupling |
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303 | if (eDsmbulk) sigma *= 2. * pow2(eDcoupling[min( abs(id1), 26)] * mH); |
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304 | else sigma *= pow2(kappaMG); |
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305 | |
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306 | // If initial quarks, 1/N_C |
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307 | if (abs(id1) < 9) sigma /= 3.; |
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308 | |
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309 | return sigma; |
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310 | } |
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311 | |
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312 | //-------------------------------------------------------------------------- |
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313 | |
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314 | // Select identity, colour and anticolour. |
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315 | |
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316 | void Sigma1ffbar2GravitonStar::setIdColAcol() { |
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317 | |
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318 | // Flavours trivial. |
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319 | setId( id1, id2, idGstar); |
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320 | |
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321 | // Colour flow topologies. Swap when antiquarks. |
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322 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0); |
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323 | else setColAcol( 0, 0, 0, 0, 0, 0); |
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324 | if (id1 < 0) swapColAcol(); |
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325 | |
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326 | } |
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327 | |
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328 | //-------------------------------------------------------------------------- |
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329 | |
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330 | // Evaluate weight for G* decay angle. |
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331 | // SA: Angle dist. for decay G* -> W/Z/h, based on |
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332 | // Phys.Rev. D65 (2002) 075008, [arXiv:hep-ph/0103308v3] |
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333 | |
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334 | double Sigma1ffbar2GravitonStar::weightDecay( Event& process, int iResBeg, |
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335 | int iResEnd) { |
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336 | |
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337 | // Identity of mother of decaying reseonance(s). |
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338 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
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339 | |
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340 | // For top decay hand over to standard routine. |
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341 | if (idMother == 6) |
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342 | return weightTopDecay( process, iResBeg, iResEnd); |
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343 | |
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344 | // G* should sit in entry 5. |
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345 | if (iResBeg != 5 || iResEnd != 5) return 1.; |
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346 | |
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347 | // Phase space factors. Reconstruct decay angle. |
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348 | double mr1 = pow2(process[6].m()) / sH; |
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349 | double mr2 = pow2(process[7].m()) / sH; |
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350 | double betaf = sqrtpos( pow2(1. - mr1 - mr2) - 4. * mr1 * mr2); |
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351 | double cosThe = (process[3].p() - process[4].p()) |
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352 | * (process[7].p() - process[6].p()) / (sH * betaf); |
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353 | |
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354 | // Default is isotropic decay. |
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355 | double wt = 1.; |
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356 | |
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357 | // Angular weight for f + fbar -> G* -> f + fbar. |
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358 | if (process[6].idAbs() < 19) { |
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359 | wt = (1. - 3. * pow2(cosThe) + 4. * pow4(cosThe)) / 2.; |
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360 | |
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361 | // Angular weight for f + fbar -> G* -> g + g or gamma + gamma. |
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362 | } else if (process[6].id() == 21 || process[6].id() == 22) { |
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363 | wt = 1. - pow4(cosThe); |
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364 | |
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365 | // Angular weight for f + fbar -> G* -> Z + Z or W + W. |
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366 | } else if (process[6].id() == 23 || process[6].id() == 24) { |
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367 | double beta2 = pow2(betaf); |
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368 | double cost2 = pow2(cosThe); |
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369 | double cost4 = pow2(cost2); |
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370 | wt = pow2(beta2 - 2.)*cost2*(1. - cost2); |
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371 | // Longitudinal W/Z only. |
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372 | if (eDvlvl) { |
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373 | wt /= 4.; |
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374 | // Transverse W/Z contributions as well. |
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375 | } else { |
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376 | wt += pow2(beta2 - 1.)*cost2*(1. - cost2); |
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377 | wt += 2.*(1. - cost4); |
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378 | wt += (1. - beta2)*(1. - 3.*cost2 + 4.*cost4); |
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379 | wt /= 8.; |
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380 | } |
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381 | |
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382 | // Angular weight for f + fbar -> G* -> h + h |
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383 | } else if (process[6].id() == 25) { |
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384 | double beta2 = pow2(betaf); |
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385 | double cost2 = pow2(cosThe); |
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386 | wt = pow2(beta2 - 2.)*cost2*(1. - cost2); |
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387 | wt /= 4.; |
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388 | } |
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389 | |
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390 | // Done. |
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391 | return wt; |
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392 | |
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393 | } |
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394 | |
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395 | //========================================================================== |
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396 | |
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397 | // Sigma1qqbar2KKgluonStar class. |
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398 | // Cross section for q qbar -> g^*/KK-gluon^* (excited KK-gluon state). |
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399 | |
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400 | //-------------------------------------------------------------------------- |
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401 | |
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402 | // Initialize process. |
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403 | |
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404 | void Sigma1qqbar2KKgluonStar::initProc() { |
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405 | |
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406 | // Store kk-gluon* mass and width for propagator. |
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407 | idKKgluon = 5100021; |
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408 | mRes = particleDataPtr->m0(idKKgluon); |
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409 | GammaRes = particleDataPtr->mWidth(idKKgluon); |
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410 | m2Res = mRes*mRes; |
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411 | GamMRat = GammaRes / mRes; |
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412 | |
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413 | // KK-gluon gv/ga couplings and interference. |
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414 | for (int i = 0; i < 10; ++i) { eDgv[i] = 0.; eDga[i] = 0.; } |
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415 | double tmPgL = settingsPtr->parm("ExtraDimensionsG*:KKgqL"); |
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416 | double tmPgR = settingsPtr->parm("ExtraDimensionsG*:KKgqR"); |
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417 | for (int i = 1; i <= 4; ++i) { |
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418 | eDgv[i] = 0.5 * (tmPgL + tmPgR); |
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419 | eDga[i] = 0.5 * (tmPgL - tmPgR); |
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420 | } |
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421 | tmPgL = settingsPtr->parm("ExtraDimensionsG*:KKgbL"); |
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422 | tmPgR = settingsPtr->parm("ExtraDimensionsG*:KKgbR"); |
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423 | eDgv[5] = 0.5 * (tmPgL + tmPgR); eDga[5] = 0.5 * (tmPgL - tmPgR); |
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424 | tmPgL = settingsPtr->parm("ExtraDimensionsG*:KKgtL"); |
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425 | tmPgR = settingsPtr->parm("ExtraDimensionsG*:KKgtR"); |
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426 | eDgv[6] = 0.5 * (tmPgL + tmPgR); eDga[6] = 0.5 * (tmPgL - tmPgR); |
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427 | interfMode = settingsPtr->mode("ExtraDimensionsG*:KKintMode"); |
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428 | |
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429 | // Set pointer to particle properties and decay table. |
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430 | gStarPtr = particleDataPtr->particleDataEntryPtr(idKKgluon); |
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431 | |
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432 | } |
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433 | |
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434 | //-------------------------------------------------------------------------- |
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435 | |
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436 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
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437 | |
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438 | void Sigma1qqbar2KKgluonStar::sigmaKin() { |
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439 | |
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440 | // Incoming width for fermions. |
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441 | double widthIn = alpS * mH * 4 / 27; |
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442 | double widthOut = alpS * mH / 6; |
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443 | |
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444 | // Loop over all decay channels. |
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445 | sumSM = 0.; |
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446 | sumInt = 0.; |
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447 | sumKK = 0.; |
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448 | |
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449 | for (int i = 0; i < gStarPtr->sizeChannels(); ++i) { |
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450 | int idAbs = abs( gStarPtr->channel(i).product(0) ); |
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451 | |
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452 | // Only contributions quarks. |
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453 | if ( idAbs > 0 && idAbs <= 6 ) { |
---|
454 | double mf = particleDataPtr->m0(idAbs); |
---|
455 | |
---|
456 | // Check that above threshold. Phase space. |
---|
457 | if (mH > 2. * mf + MASSMARGIN) { |
---|
458 | double mr = pow2(mf / mH); |
---|
459 | double beta = sqrtpos(1. - 4. * mr); |
---|
460 | |
---|
461 | // Store sum of combinations. For outstate only open channels. |
---|
462 | int onMode = gStarPtr->channel(i).onMode(); |
---|
463 | if (onMode == 1 || onMode == 2) { |
---|
464 | sumSM += beta * (1. + 2. * mr); |
---|
465 | sumInt += beta * eDgv[min(idAbs, 9)] * (1. + 2. * mr); |
---|
466 | sumKK += beta * (pow2(eDgv[min(idAbs, 9)]) * (1. + 2.*mr) |
---|
467 | + pow2(eDga[min(idAbs, 9)]) * (1. - 4.*mr)); |
---|
468 | } |
---|
469 | } |
---|
470 | } |
---|
471 | } |
---|
472 | |
---|
473 | // Set up Breit-Wigner. Width out only includes open channels. |
---|
474 | sigSM = widthIn * 12. * M_PI * widthOut / sH2; |
---|
475 | sigInt = 2. * sigSM * sH * (sH - m2Res) |
---|
476 | / ( pow2(sH - m2Res) + pow2(sH * GamMRat) ); |
---|
477 | sigKK = sigSM * sH2 / ( pow2(sH - m2Res) + pow2(sH * GamMRat) ); |
---|
478 | |
---|
479 | // Optionally only keep g* or gKK term. |
---|
480 | if (interfMode == 1) {sigInt = 0.; sigKK = 0.;} |
---|
481 | if (interfMode == 2) {sigSM = 0.; sigInt = 0.;} |
---|
482 | |
---|
483 | } |
---|
484 | |
---|
485 | //-------------------------------------------------------------------------- |
---|
486 | |
---|
487 | // Evaluate sigmaHat(sHat), part dependent of incoming flavour. |
---|
488 | |
---|
489 | double Sigma1qqbar2KKgluonStar::sigmaHat() { |
---|
490 | |
---|
491 | // RS graviton coupling. |
---|
492 | double sigma = sigSM * sumSM |
---|
493 | + eDgv[min(abs(id1), 9)] * sigInt * sumInt |
---|
494 | + ( pow2(eDgv[min(abs(id1), 9)]) |
---|
495 | + pow2(eDga[min(abs(id1), 9)]) ) * sigKK * sumKK; |
---|
496 | |
---|
497 | return sigma; |
---|
498 | } |
---|
499 | |
---|
500 | //-------------------------------------------------------------------------- |
---|
501 | |
---|
502 | // Select identity, colour and anticolour. |
---|
503 | |
---|
504 | void Sigma1qqbar2KKgluonStar::setIdColAcol() { |
---|
505 | |
---|
506 | // Flavours trivial. |
---|
507 | setId( id1, id2, idKKgluon); |
---|
508 | |
---|
509 | // Colour flow topologies. Swap when antiquarks. |
---|
510 | setColAcol( 1, 0, 0, 2, 1, 2); |
---|
511 | if (id1 < 0) swapColAcol(); |
---|
512 | |
---|
513 | } |
---|
514 | |
---|
515 | //-------------------------------------------------------------------------- |
---|
516 | |
---|
517 | // Evaluate weight for KK-gluon* decay angle (based on ffbar2gmZ). |
---|
518 | |
---|
519 | double Sigma1qqbar2KKgluonStar::weightDecay( Event& process, int iResBeg, |
---|
520 | int iResEnd) { |
---|
521 | |
---|
522 | // Identity of mother of decaying reseonance(s). |
---|
523 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
---|
524 | |
---|
525 | // For top decay hand over to standard routine. |
---|
526 | if (idMother == 6) |
---|
527 | return weightTopDecay( process, iResBeg, iResEnd); |
---|
528 | |
---|
529 | // g* should sit in entry 5. |
---|
530 | if (iResBeg != 5 || iResEnd != 5) return 1.; |
---|
531 | |
---|
532 | // Couplings for in- and out-flavours (alpS already included). |
---|
533 | int idInAbs = process[3].idAbs(); |
---|
534 | double vi = eDgv[min(idInAbs, 9)]; |
---|
535 | double ai = eDga[min(idInAbs, 9)]; |
---|
536 | int idOutAbs = process[6].idAbs(); |
---|
537 | double vf = eDgv[min(idOutAbs, 9)]; |
---|
538 | double af = eDga[min(idOutAbs, 9)]; |
---|
539 | |
---|
540 | // Phase space factors. (One power of beta left out in formulae.) |
---|
541 | double mf = process[6].m(); |
---|
542 | double mr = mf*mf / sH; |
---|
543 | double betaf = sqrtpos(1. - 4. * mr); |
---|
544 | |
---|
545 | // Coefficients of angular expression. |
---|
546 | double coefTran = sigSM + vi * sigInt * vf |
---|
547 | + (vi*vi + ai*ai) * sigKK * (vf*vf + pow2(betaf) * af*af); |
---|
548 | double coefLong = 4. * mr * ( sigSM + vi * sigInt * vf |
---|
549 | + (vi*vi + ai*ai) * sigKK * vf*vf ); |
---|
550 | double coefAsym = betaf * ( ai * sigInt * af |
---|
551 | + 4. * vi * ai * sigKK * vf * af ); |
---|
552 | |
---|
553 | // Flip asymmetry for in-fermion + out-antifermion. |
---|
554 | if (process[3].id() * process[6].id() < 0) coefAsym = -coefAsym; |
---|
555 | |
---|
556 | // Reconstruct decay angle and weight for it. |
---|
557 | double cosThe = (process[3].p() - process[4].p()) |
---|
558 | * (process[7].p() - process[6].p()) / (sH * betaf); |
---|
559 | double wtMax = 2. * (coefTran + abs(coefAsym)); |
---|
560 | double wt = coefTran * (1. + pow2(cosThe)) |
---|
561 | + coefLong * (1. - pow2(cosThe)) + 2. * coefAsym * cosThe; |
---|
562 | |
---|
563 | // Done. |
---|
564 | return (wt / wtMax); |
---|
565 | } |
---|
566 | |
---|
567 | //========================================================================== |
---|
568 | |
---|
569 | // Sigma2gg2GravitonStarg class. |
---|
570 | // Cross section for g g -> G* g (excited graviton state). |
---|
571 | |
---|
572 | //-------------------------------------------------------------------------- |
---|
573 | |
---|
574 | // Initialize process. |
---|
575 | |
---|
576 | void Sigma2gg2GravitonStarg::initProc() { |
---|
577 | |
---|
578 | // Store G* mass and width for propagator. |
---|
579 | idGstar = 5100039; |
---|
580 | mRes = particleDataPtr->m0(idGstar); |
---|
581 | GammaRes = particleDataPtr->mWidth(idGstar); |
---|
582 | m2Res = mRes*mRes; |
---|
583 | GamMRat = GammaRes / mRes; |
---|
584 | |
---|
585 | // Overall coupling strength kappa * m_G*. |
---|
586 | kappaMG = settingsPtr->parm("ExtraDimensionsG*:kappaMG"); |
---|
587 | |
---|
588 | // Secondary open width fraction. |
---|
589 | openFrac = particleDataPtr->resOpenFrac(idGstar); |
---|
590 | |
---|
591 | } |
---|
592 | |
---|
593 | //-------------------------------------------------------------------------- |
---|
594 | |
---|
595 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
---|
596 | |
---|
597 | void Sigma2gg2GravitonStarg::sigmaKin() { |
---|
598 | |
---|
599 | // Evaluate cross section. Secondary width for G*. |
---|
600 | sigma = (3. * pow2(kappaMG) * alpS) / (32. * sH * s3) |
---|
601 | * ( pow2(tH2 + tH * uH + uH2) / (sH2 * tH * uH) |
---|
602 | + 2. * (tH2 / uH + uH2 / tH) / sH + 3. * (tH / uH + uH / tH) |
---|
603 | + 2. * (sH / uH + sH/tH) + sH2 / (tH * uH) ); |
---|
604 | sigma *= openFrac; |
---|
605 | |
---|
606 | } |
---|
607 | |
---|
608 | //-------------------------------------------------------------------------- |
---|
609 | |
---|
610 | // Select identity, colour and anticolour. |
---|
611 | |
---|
612 | void Sigma2gg2GravitonStarg::setIdColAcol() { |
---|
613 | |
---|
614 | // Flavours trivial. |
---|
615 | setId( 21, 21, idGstar, 21); |
---|
616 | |
---|
617 | // Colour flow topologies: random choice between two mirrors. |
---|
618 | if (rndmPtr->flat() < 0.5) setColAcol( 1, 2, 2, 3, 0, 0, 1, 3); |
---|
619 | else setColAcol( 1, 2, 3, 1, 0, 0, 3, 2); |
---|
620 | |
---|
621 | } |
---|
622 | |
---|
623 | //-------------------------------------------------------------------------- |
---|
624 | |
---|
625 | // Evaluate weight for decay angles: currently G* assumed isotropic. |
---|
626 | |
---|
627 | double Sigma2gg2GravitonStarg::weightDecay( Event& process, int iResBeg, |
---|
628 | int iResEnd) { |
---|
629 | |
---|
630 | // Identity of mother of decaying reseonance(s). |
---|
631 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
---|
632 | |
---|
633 | // For top decay hand over to standard routine. |
---|
634 | if (idMother == 6) |
---|
635 | return weightTopDecay( process, iResBeg, iResEnd); |
---|
636 | |
---|
637 | // No equations for G* decay so assume isotropic. |
---|
638 | return 1.; |
---|
639 | |
---|
640 | } |
---|
641 | |
---|
642 | //========================================================================== |
---|
643 | |
---|
644 | // Sigma2qg2GravitonStarq class. |
---|
645 | // Cross section for q g -> G* q (excited graviton state). |
---|
646 | |
---|
647 | //-------------------------------------------------------------------------- |
---|
648 | |
---|
649 | // Initialize process. |
---|
650 | |
---|
651 | void Sigma2qg2GravitonStarq::initProc() { |
---|
652 | |
---|
653 | // Store G* mass and width for propagator. |
---|
654 | idGstar = 5100039; |
---|
655 | mRes = particleDataPtr->m0(idGstar); |
---|
656 | GammaRes = particleDataPtr->mWidth(idGstar); |
---|
657 | m2Res = mRes*mRes; |
---|
658 | GamMRat = GammaRes / mRes; |
---|
659 | |
---|
660 | // Overall coupling strength kappa * m_G*. |
---|
661 | kappaMG = settingsPtr->parm("ExtraDimensionsG*:kappaMG"); |
---|
662 | |
---|
663 | // Secondary open width fraction. |
---|
664 | openFrac = particleDataPtr->resOpenFrac(idGstar); |
---|
665 | |
---|
666 | } |
---|
667 | |
---|
668 | //-------------------------------------------------------------------------- |
---|
669 | |
---|
670 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
---|
671 | |
---|
672 | void Sigma2qg2GravitonStarq::sigmaKin() { |
---|
673 | |
---|
674 | // Evaluate cross section. Secondary width for G*. |
---|
675 | sigma = -(pow2(kappaMG) * alpS) / (192. * sH * s3) |
---|
676 | * ( 4. * (sH2 + uH2) / (tH * sH) + 9. * (sH + uH) / sH + sH / uH |
---|
677 | + uH2 / sH2 + 3. * tH * (4. + sH / uH + uH / sH) / sH |
---|
678 | + 4. * tH2 * (1. / uH + 1. / sH) / sH + 2. * tH2 * tH / (uH * sH2) ); |
---|
679 | sigma *= openFrac; |
---|
680 | |
---|
681 | } |
---|
682 | |
---|
683 | //-------------------------------------------------------------------------- |
---|
684 | |
---|
685 | // Select identity, colour and anticolour. |
---|
686 | |
---|
687 | void Sigma2qg2GravitonStarq::setIdColAcol() { |
---|
688 | |
---|
689 | // Flavour set up for q g -> H q. |
---|
690 | int idq = (id2 == 21) ? id1 : id2; |
---|
691 | setId( id1, id2, idGstar, idq); |
---|
692 | |
---|
693 | // tH defined between f and f': must swap tHat <-> uHat if q g in. |
---|
694 | swapTU = (id2 == 21); |
---|
695 | |
---|
696 | // Colour flow topologies. Swap when antiquarks. |
---|
697 | if (id2 == 21) setColAcol( 1, 0, 2, 1, 0, 0, 2, 0); |
---|
698 | else setColAcol( 2, 1, 1, 0, 0, 0, 2, 0); |
---|
699 | if (idq < 0) swapColAcol(); |
---|
700 | |
---|
701 | } |
---|
702 | |
---|
703 | //-------------------------------------------------------------------------- |
---|
704 | |
---|
705 | // Evaluate weight for decay angles: currently G* assumed isotropic. |
---|
706 | |
---|
707 | double Sigma2qg2GravitonStarq::weightDecay( Event& process, int iResBeg, |
---|
708 | int iResEnd) { |
---|
709 | |
---|
710 | // Identity of mother of decaying reseonance(s). |
---|
711 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
---|
712 | |
---|
713 | // For top decay hand over to standard routine. |
---|
714 | if (idMother == 6) |
---|
715 | return weightTopDecay( process, iResBeg, iResEnd); |
---|
716 | |
---|
717 | // No equations for G* decay so assume isotropic. |
---|
718 | return 1.; |
---|
719 | |
---|
720 | } |
---|
721 | |
---|
722 | //========================================================================== |
---|
723 | |
---|
724 | // Sigma2qqbar2GravitonStarg class. |
---|
725 | // Cross section for q qbar -> G* g (excited graviton state). |
---|
726 | |
---|
727 | //-------------------------------------------------------------------------- |
---|
728 | |
---|
729 | // Initialize process. |
---|
730 | |
---|
731 | void Sigma2qqbar2GravitonStarg::initProc() { |
---|
732 | |
---|
733 | // Store G* mass and width for propagator. |
---|
734 | idGstar = 5100039; |
---|
735 | mRes = particleDataPtr->m0(idGstar); |
---|
736 | GammaRes = particleDataPtr->mWidth(idGstar); |
---|
737 | m2Res = mRes*mRes; |
---|
738 | GamMRat = GammaRes / mRes; |
---|
739 | |
---|
740 | // Overall coupling strength kappa * m_G*. |
---|
741 | kappaMG = settingsPtr->parm("ExtraDimensionsG*:kappaMG"); |
---|
742 | |
---|
743 | // Secondary open width fraction. |
---|
744 | openFrac = particleDataPtr->resOpenFrac(idGstar); |
---|
745 | |
---|
746 | } |
---|
747 | |
---|
748 | //-------------------------------------------------------------------------- |
---|
749 | |
---|
750 | // Evaluate sigmaHat(sHat), part independent of incoming flavour. |
---|
751 | |
---|
752 | void Sigma2qqbar2GravitonStarg::sigmaKin() { |
---|
753 | |
---|
754 | // Evaluate cross section. Secondary width for G*. |
---|
755 | sigma = (pow2(kappaMG) * alpS) / (72. * sH * s3) |
---|
756 | * ( 4. * (tH2 + uH2) / sH2 + 9. * (tH + uH) / sH |
---|
757 | + (tH2 / uH + uH2 / tH) / sH + 3. * (4. + tH / uH + uH/ tH) |
---|
758 | + 4. * (sH / uH + sH / tH) + 2. * sH2 / (tH * uH) ); |
---|
759 | sigma *= openFrac; |
---|
760 | |
---|
761 | } |
---|
762 | |
---|
763 | //-------------------------------------------------------------------------- |
---|
764 | |
---|
765 | // Select identity, colour and anticolour. |
---|
766 | |
---|
767 | void Sigma2qqbar2GravitonStarg::setIdColAcol() { |
---|
768 | |
---|
769 | // Flavours trivial. |
---|
770 | setId( id1, id2, idGstar, 21); |
---|
771 | |
---|
772 | // Colour flow topologies. Swap when antiquarks. |
---|
773 | setColAcol( 1, 0, 0, 2, 0, 0, 1, 2); |
---|
774 | if (id1 < 0) swapColAcol(); |
---|
775 | |
---|
776 | } |
---|
777 | |
---|
778 | //-------------------------------------------------------------------------- |
---|
779 | |
---|
780 | // Evaluate weight for decay angles: currently G* assumed isotropic. |
---|
781 | |
---|
782 | double Sigma2qqbar2GravitonStarg::weightDecay( Event& process, int iResBeg, |
---|
783 | int iResEnd) { |
---|
784 | |
---|
785 | // Identity of mother of decaying reseonance(s). |
---|
786 | int idMother = process[process[iResBeg].mother1()].idAbs(); |
---|
787 | |
---|
788 | // For top decay hand over to standard routine. |
---|
789 | if (idMother == 6) |
---|
790 | return weightTopDecay( process, iResBeg, iResEnd); |
---|
791 | |
---|
792 | // No equations for G* decay so assume isotropic. |
---|
793 | return 1.; |
---|
794 | |
---|
795 | } |
---|
796 | |
---|
797 | //========================================================================== |
---|
798 | |
---|
799 | // NOAM: Sigma2ffbar2TEVffbar class. |
---|
800 | // Cross section for, f fbar -> gammaKK/ZKK -> F Fbar. |
---|
801 | // Process provided by N. Hod et al. and is described in arXiv:XXXX.YYYY |
---|
802 | |
---|
803 | //-------------------------------------------------------------------------- |
---|
804 | |
---|
805 | // Initialize process. |
---|
806 | |
---|
807 | void Sigma2ffbar2TEVffbar::initProc() { |
---|
808 | |
---|
809 | // Process name. |
---|
810 | if (idNew == 1) nameSave = "f fbar -> d dbar (s-channel gamma_KK/Z_KK)"; |
---|
811 | if (idNew == 2) nameSave = "f fbar -> u ubar (s-channel gamma_KK/Z_KK)"; |
---|
812 | if (idNew == 3) nameSave = "f fbar -> s sbar (s-channel gamma_KK/Z_KK)"; |
---|
813 | if (idNew == 4) nameSave = "f fbar -> c cbar (s-channel gamma_KK/Z_KK)"; |
---|
814 | if (idNew == 5) nameSave = "f fbar -> b bbar (s-channel gamma_KK/Z_KK)"; |
---|
815 | if (idNew == 6) nameSave = "f fbar -> t tbar (s-channel gamma_KK/Z_KK)"; |
---|
816 | if (idNew == 11) nameSave = "f fbar -> e+ e- (s-channel gamma_KK/Z_KK)"; |
---|
817 | if (idNew == 12) nameSave = "f fbar -> nue nuebar (s-channel gamma_KK/Z_KK)"; |
---|
818 | if (idNew == 13) nameSave = "f fbar -> mu+ mu- (s-channel gamma_KK/Z_KK)"; |
---|
819 | if (idNew == 14) nameSave |
---|
820 | = "f fbar -> numu numubar (s-channel gamma_KK/Z_KK)"; |
---|
821 | if (idNew == 15) nameSave = "f fbar -> tau+ tau- (s-channel gamma_KK/Z_KK)"; |
---|
822 | if (idNew == 16) nameSave |
---|
823 | = "f fbar -> nutau nutaubar (s-channel gamma_KK/Z_KK)"; |
---|
824 | |
---|
825 | // Allow to pick only gamma* or Z0 part of full gamma*/Z0 expression. |
---|
826 | gmZmode = settingsPtr->mode("ExtraDimensionsTEV:gmZmode"); |
---|
827 | |
---|
828 | // Pick number of KK excitations |
---|
829 | nexcitationmax = (int)settingsPtr->parm("ExtraDimensionsTEV:nMax"); |
---|
830 | |
---|
831 | // Initialize the widths of the KK propogators. |
---|
832 | // partial width of the KK photon |
---|
833 | wgmKKFactor = 0.; |
---|
834 | // total width of the KK photon |
---|
835 | wgmKKn = 0.; |
---|
836 | // will be proportional to "wZ0" + ttbar addition |
---|
837 | wZKKn = 0.; |
---|
838 | |
---|
839 | // Store Z0 mass and width for propagator. |
---|
840 | wZ0 = particleDataPtr->mWidth(23); |
---|
841 | mRes = particleDataPtr->m0(23); |
---|
842 | m2Res = mRes*mRes; |
---|
843 | |
---|
844 | // Store the top mass for the ttbar width calculations |
---|
845 | mTop = particleDataPtr->m0(6); |
---|
846 | m2Top = mTop*mTop; |
---|
847 | |
---|
848 | // Store the KK mass parameter, equivalent to the mass of the first KK |
---|
849 | // excitation: particleDataPtr->m0(5000023); |
---|
850 | mStar = (double)settingsPtr->parm("ExtraDimensionsTEV:mStar"); |
---|
851 | |
---|
852 | // Get alphaEM - relevant for the calculation of the widths |
---|
853 | alphaemfixed = settingsPtr->parm("StandardModel:alphaEM0"); |
---|
854 | |
---|
855 | // initialize imaginari number |
---|
856 | mI = complex(0.,1.); |
---|
857 | |
---|
858 | // Sum all partial widths of the KK photon except for the ttbar channel |
---|
859 | // which is handeled afterwards seperately |
---|
860 | if (gmZmode>=0 && gmZmode<=5) { |
---|
861 | for (int i=1 ; i<17 ; i++) { |
---|
862 | if (i==7) { i=11; } |
---|
863 | // skip the ttbar decay and add its contribution later |
---|
864 | if (i==6) { continue; } |
---|
865 | if (i<9) { |
---|
866 | wgmKKFactor += ( (alphaemfixed / 6.) * 4. |
---|
867 | * couplingsPtr->ef(i) * couplingsPtr->ef(i) * 3. ); |
---|
868 | } |
---|
869 | else { |
---|
870 | wgmKKFactor += (alphaemfixed / 6.) * 4. |
---|
871 | * couplingsPtr->ef(i) * couplingsPtr->ef(i); |
---|
872 | } |
---|
873 | } |
---|
874 | } |
---|
875 | |
---|
876 | // Get the helicity-couplings of the Z0 to all the fermions except top |
---|
877 | gMinusF = ( couplingsPtr->t3f(idNew) - couplingsPtr->ef(idNew) |
---|
878 | * couplingsPtr->sin2thetaW() ) |
---|
879 | / sqrt( couplingsPtr->sin2thetaW()*couplingsPtr->cos2thetaW() ); |
---|
880 | gPlusF = -1. * couplingsPtr->ef(idNew) * couplingsPtr->sin2thetaW() |
---|
881 | / sqrt( couplingsPtr->sin2thetaW() * couplingsPtr->cos2thetaW() ); |
---|
882 | // Get the helicity-couplings of the Z0 to the top quark |
---|
883 | gMinusTop = ( couplingsPtr->t3f(6) - couplingsPtr->ef(6) |
---|
884 | * couplingsPtr->sin2thetaW() ) |
---|
885 | / sqrt( couplingsPtr->sin2thetaW()*couplingsPtr->cos2thetaW() ); |
---|
886 | |
---|
887 | gPlusTop = -1. * couplingsPtr->ef(6) * couplingsPtr->sin2thetaW() |
---|
888 | / sqrt( couplingsPtr->sin2thetaW() * couplingsPtr->cos2thetaW() ); |
---|
889 | // calculate the constant factor of the unique ttbar decay width |
---|
890 | ttbarwFactorA = pow2(gMinusTop) + pow2(gPlusTop); |
---|
891 | ttbarwFactorB = 6.*gMinusTop*gPlusTop - pow2(gMinusTop) - pow2(gPlusTop); |
---|
892 | |
---|
893 | // Secondary open width fraction, relevant for top (or heavier). |
---|
894 | openFracPair = 1.; |
---|
895 | if ((idNew >=6 && idNew <=8) || idNew == 17 || idNew == 18) |
---|
896 | openFracPair = particleDataPtr->resOpenFrac(idNew, -idNew); |
---|
897 | |
---|
898 | } |
---|
899 | |
---|
900 | //-------------------------------------------------------------------------- |
---|
901 | |
---|
902 | // For improving the phase-space sampling (there can be 2 resonances) |
---|
903 | |
---|
904 | int Sigma2ffbar2TEVffbar::resonanceB() { |
---|
905 | |
---|
906 | return 23; |
---|
907 | |
---|
908 | } |
---|
909 | |
---|
910 | //-------------------------------------------------------------------------- |
---|
911 | |
---|
912 | // For improving the phase-space sampling (there can be 2 resonances) |
---|
913 | |
---|
914 | int Sigma2ffbar2TEVffbar::resonanceA() { |
---|
915 | |
---|
916 | if (gmZmode>=3) { |
---|
917 | phaseSpacemHatMin = settingsPtr->parm("PhaseSpace:mHatMin"); |
---|
918 | phaseSpacemHatMax = settingsPtr->parm("PhaseSpace:mHatMax"); |
---|
919 | double mResFirstKKMode = sqrt(pow2(particleDataPtr->m0(23)) + pow2(mStar)); |
---|
920 | if (mResFirstKKMode/2. <= phaseSpacemHatMax |
---|
921 | || 3*mResFirstKKMode/2. >= phaseSpacemHatMin) { return 5000023; } |
---|
922 | else { return 23; } |
---|
923 | // no KK terms at all |
---|
924 | } else { return 23; } |
---|
925 | |
---|
926 | } |
---|
927 | |
---|
928 | //-------------------------------------------------------------------------- |
---|
929 | |
---|
930 | // Evaluate d(sigmaHat)/d(tHat), part independent of incoming flavour. |
---|
931 | |
---|
932 | void Sigma2ffbar2TEVffbar::sigmaKin() { |
---|
933 | |
---|
934 | // Check that above threshold. |
---|
935 | isPhysical = true; |
---|
936 | if (mH < m3 + m4 + MASSMARGIN) { |
---|
937 | isPhysical = false; |
---|
938 | return; |
---|
939 | } |
---|
940 | |
---|
941 | // Define average F, Fbar mass so same beta. Phase space. |
---|
942 | double s34Avg = 0.5 * (s3 + s4) - 0.25 * pow2(s3 - s4) / sH; |
---|
943 | mr = s34Avg / sH; |
---|
944 | betaf = sqrtpos(1. - 4. * mr); |
---|
945 | |
---|
946 | // Reconstruct decay angle so can reuse 2 -> 1 cross section. |
---|
947 | cosThe = (tH - uH) / (betaf * sH); |
---|
948 | |
---|
949 | } |
---|
950 | |
---|
951 | //-------------------------------------------------------------------------- |
---|
952 | |
---|
953 | // Evaluate d(sigmaHat)/d(tHat), including incoming flavour dependence. |
---|
954 | |
---|
955 | double Sigma2ffbar2TEVffbar::sigmaHat() { |
---|
956 | |
---|
957 | // Fail if below threshold. |
---|
958 | if (!isPhysical) return 0.; |
---|
959 | |
---|
960 | // Couplings for in/out-flavours. |
---|
961 | int idAbs = abs(id1); |
---|
962 | |
---|
963 | // The couplings of the Z0 to the fermions for in/out flavors |
---|
964 | gMinusf = ( couplingsPtr->t3f(idAbs) - couplingsPtr->ef(idAbs) |
---|
965 | * couplingsPtr->sin2thetaW() ) |
---|
966 | / sqrt( couplingsPtr->sin2thetaW()*couplingsPtr->cos2thetaW() ); |
---|
967 | gPlusf = -1. * couplingsPtr->ef(idAbs)*couplingsPtr->sin2thetaW() |
---|
968 | / sqrt( couplingsPtr->sin2thetaW()*couplingsPtr->cos2thetaW() ); |
---|
969 | |
---|
970 | // Initialize the some values |
---|
971 | helicityME2 = 0.; |
---|
972 | coefAngular = 0.; |
---|
973 | gf=0.; |
---|
974 | gF=0.; |
---|
975 | gammaProp = complex(0.,0.); |
---|
976 | resProp = complex(0.,0.); |
---|
977 | gmPropKK = complex(0.,0.); |
---|
978 | ZPropKK = complex(0.,0.); |
---|
979 | totalProp = complex(0.,0.); |
---|
980 | |
---|
981 | // Sum all initial and final helicity states this corresponds to an |
---|
982 | // unpolarized beams and unmeasured polarization final-state |
---|
983 | for (double helicityf=-0.5 ; helicityf<=0.5 ; helicityf++) { |
---|
984 | for (double helicityF=-0.5 ; helicityF<=0.5 ; helicityF++) { |
---|
985 | // the couplings for the initial-final helicity configuration |
---|
986 | gF = (helicityF == +0.5) ? gMinusF : gPlusF; |
---|
987 | gf = (helicityf == +0.5) ? gMinusf : gPlusf; |
---|
988 | // 0=SM gmZ, 1=SM gm, 2=SM Z, 3=SM+KK gmZ, 4=KK gm, 5=KK Z |
---|
989 | switch(gmZmode) { |
---|
990 | // SM photon and Z0 only |
---|
991 | case 0: |
---|
992 | gammaProp = couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)/sH; |
---|
993 | resProp = gf*gF/( sH - m2Res + mI*sH*(wZ0/mRes) ); |
---|
994 | break; |
---|
995 | // SM photon only |
---|
996 | case 1: |
---|
997 | gammaProp = couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)/sH; |
---|
998 | break; |
---|
999 | // SM Z0 only |
---|
1000 | case 2: |
---|
1001 | resProp = gf*gF/( sH - m2Res + mI*sH*(wZ0/mRes) ); |
---|
1002 | break; |
---|
1003 | // KK photon and Z |
---|
1004 | case 3: |
---|
1005 | gammaProp = couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)/sH; |
---|
1006 | resProp = gf*gF/( sH - m2Res + mI*sH*(wZ0/mRes) ); |
---|
1007 | ZPropKK = complex(0.,0.); |
---|
1008 | gmPropKK = complex(0.,0.); |
---|
1009 | // Sum all KK excitations contributions |
---|
1010 | for(int nexcitation = 1; nexcitation <= nexcitationmax; |
---|
1011 | nexcitation++) { |
---|
1012 | mZKKn = sqrt(m2Res + pow2(mStar * nexcitation)); |
---|
1013 | m2ZKKn = m2Res + pow2(mStar * nexcitation); |
---|
1014 | mgmKKn = mStar * nexcitation; |
---|
1015 | m2gmKKn = (mStar*nexcitation)*(mStar*nexcitation); |
---|
1016 | // calculate the width of the n'th excitation of the KK Z |
---|
1017 | // (proportional to the Z0 width + ttbar partial width) |
---|
1018 | ttbarwZKKn = 2.*(alphaemfixed*3./6.)*mZKKn |
---|
1019 | * sqrt(1.-4.*m2Top/m2ZKKn) |
---|
1020 | * (ttbarwFactorA+(m2Top/m2ZKKn)*ttbarwFactorB); |
---|
1021 | wZKKn = 2.*wZ0*mZKKn/mRes+ttbarwZKKn; |
---|
1022 | // calculate the width of the n'th excitation of the |
---|
1023 | // KK photon |
---|
1024 | ttbarwgmKKn = 2.*(alphaemfixed*3./6.)*mgmKKn |
---|
1025 | * sqrt(1.-4.*m2Top/m2gmKKn) |
---|
1026 | * 2.*pow2(couplingsPtr->ef(6))*(1.+2.*(m2Top/m2gmKKn)); |
---|
1027 | wgmKKn = wgmKKFactor*mgmKKn+ttbarwgmKKn; |
---|
1028 | // the propogators |
---|
1029 | gmPropKK += (2.*couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)) |
---|
1030 | / (sH-m2gmKKn+mI*sH*wgmKKn/mgmKKn); |
---|
1031 | ZPropKK += (2.*gf*gF)/(sH-m2ZKKn+mI*sH*wZKKn/mZKKn ); |
---|
1032 | } |
---|
1033 | break; |
---|
1034 | // SM photon and Z0 with KK photon only |
---|
1035 | case 4: |
---|
1036 | gammaProp = couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)/sH; |
---|
1037 | resProp = gf*gF/( sH - m2Res + mI*sH*(wZ0/mRes) ); |
---|
1038 | gmPropKK = complex(0.,0.); |
---|
1039 | for (int nexcitation = 1; nexcitation <= nexcitationmax; |
---|
1040 | nexcitation++ ) { |
---|
1041 | mgmKKn = mStar * nexcitation; |
---|
1042 | m2gmKKn = (mStar*nexcitation)*(mStar*nexcitation); |
---|
1043 | |
---|
1044 | ttbarwgmKKn = 2.*(alphaemfixed*3./6.)*mgmKKn |
---|
1045 | * sqrt(1.-4.*m2Top/m2gmKKn) |
---|
1046 | * 2.*pow2(couplingsPtr->ef(6)) |
---|
1047 | * (1.+2.*(m2Top/m2gmKKn)); |
---|
1048 | wgmKKn = wgmKKFactor*mgmKKn+ttbarwgmKKn; |
---|
1049 | gmPropKK += (2.*couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)) |
---|
1050 | / (sH-m2gmKKn+mI*sH*wgmKKn/mgmKKn); |
---|
1051 | } |
---|
1052 | break; |
---|
1053 | // SM photon and Z0 with KK Z only |
---|
1054 | case 5: |
---|
1055 | gammaProp = couplingsPtr->ef(idAbs)*couplingsPtr->ef(idNew)/sH; |
---|
1056 | resProp = gf*gF/( sH - m2Res + mI*sH*(wZ0/mRes) ); |
---|
1057 | ZPropKK = complex(0.,0.); |
---|
1058 | for (int nexcitation = 1; nexcitation <= nexcitationmax; |
---|
1059 | nexcitation++ ) { |
---|
1060 | mZKKn = sqrt(m2Res + pow2(mStar * nexcitation)); |
---|
1061 | m2ZKKn = m2Res + pow2(mStar * nexcitation); |
---|
1062 | |
---|
1063 | ttbarwZKKn = 2.*(alphaemfixed*3./6.)*mZKKn |
---|
1064 | * sqrt(1.-4.*m2Top/m2ZKKn) |
---|
1065 | * (ttbarwFactorA+(m2Top/m2ZKKn)*ttbarwFactorB); |
---|
1066 | wZKKn = 2.*wZ0*mZKKn/mRes+ttbarwZKKn; |
---|
1067 | ZPropKK += (2.*gf*gF)/(sH-m2ZKKn+mI*sH*wZKKn/mZKKn ); |
---|
1068 | } |
---|
1069 | break; |
---|
1070 | default: break; |
---|
1071 | // end run over initial and final helicity states |
---|
1072 | } |
---|
1073 | |
---|
1074 | // sum all contributing amplitudes |
---|
1075 | totalProp = gammaProp + resProp + ZPropKK + gmPropKK; |
---|
1076 | |
---|
1077 | // angular distribution for the helicity configuration |
---|
1078 | coefAngular = 1. + 4. * helicityF * helicityf * cosThe; |
---|
1079 | |
---|
1080 | // the squared helicity matrix element |
---|
1081 | helicityME2 += real(totalProp*conj(totalProp))*pow2(coefAngular); |
---|
1082 | } |
---|
1083 | } |
---|
1084 | |
---|
1085 | // calculate the coefficient of the squared helicity matrix element. |
---|
1086 | coefTot = (2./sH) * 2*M_PI * pow2(alpEM)/(4.*sH) * pow2(sH)/4.; |
---|
1087 | |
---|
1088 | // the full squared helicity matrix element. |
---|
1089 | double sigma = helicityME2 * coefTot; |
---|
1090 | |
---|
1091 | // Top: corrections for closed decay channels. |
---|
1092 | sigma *= openFracPair; |
---|
1093 | |
---|
1094 | // Initial-state colour factor. Answer. |
---|
1095 | if (idAbs < 9) sigma /= 3.; |
---|
1096 | |
---|
1097 | // Final-state colour factor. Answer. |
---|
1098 | if (idNew < 9) sigma *= 3.*(1.+alpS/M_PI); |
---|
1099 | |
---|
1100 | return sigma; |
---|
1101 | } |
---|
1102 | |
---|
1103 | //-------------------------------------------------------------------------- |
---|
1104 | |
---|
1105 | // Select identity, colour and anticolour. |
---|
1106 | |
---|
1107 | void Sigma2ffbar2TEVffbar::setIdColAcol() { |
---|
1108 | |
---|
1109 | // Set outgoing flavours. |
---|
1110 | id3 = (id1 > 0) ? idNew : -idNew; |
---|
1111 | setId( id1, id2, id3, -id3); |
---|
1112 | |
---|
1113 | // Colour flow topologies. Swap when antiquarks. |
---|
1114 | if (abs(id1) < 9 && idNew < 9) setColAcol( 1, 0, 0, 1, 2, 0, 0, 2); |
---|
1115 | else if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0, 0, 0); |
---|
1116 | else if (idNew < 9) setColAcol( 0, 0, 0, 0, 1, 0, 0, 1); |
---|
1117 | else setColAcol( 0, 0, 0, 0, 0, 0, 0, 0); |
---|
1118 | if (id1 < 0) swapColAcol(); |
---|
1119 | |
---|
1120 | } |
---|
1121 | |
---|
1122 | //-------------------------------------------------------------------------- |
---|
1123 | |
---|
1124 | // Evaluate weight for decay angles of W in top decay. |
---|
1125 | |
---|
1126 | double Sigma2ffbar2TEVffbar::weightDecay( Event& process, int iResBeg, |
---|
1127 | int iResEnd) { |
---|
1128 | |
---|
1129 | // For top decay hand over to standard routine, else done. |
---|
1130 | if (idNew == 6 && process[process[iResBeg].mother1()].idAbs() == 6) |
---|
1131 | return weightTopDecay( process, iResBeg, iResEnd); |
---|
1132 | else return 1.; |
---|
1133 | |
---|
1134 | } |
---|
1135 | |
---|
1136 | //========================================================================== |
---|
1137 | |
---|
1138 | // Sigma2gg2LEDUnparticleg class. |
---|
1139 | // Cross section for g g -> U/G g (real graviton emission in |
---|
1140 | // large extra dimensions or unparticle emission). |
---|
1141 | |
---|
1142 | //-------------------------------------------------------------------------- |
---|
1143 | |
---|
1144 | void Sigma2gg2LEDUnparticleg::initProc() { |
---|
1145 | |
---|
1146 | // Init model parameters. |
---|
1147 | eDidG = 5000039; |
---|
1148 | if (eDgraviton) { |
---|
1149 | eDspin = (settingsPtr->flag("ExtraDimensionsLED:GravScalar")) ? 0 : 2; |
---|
1150 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
1151 | eDdU = 0.5 * eDnGrav + 1; |
---|
1152 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
1153 | eDlambda = 1; |
---|
1154 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
1155 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
1156 | eDcf = settingsPtr->parm("ExtraDimensionsLED:c"); |
---|
1157 | } else { |
---|
1158 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
1159 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
1160 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
1161 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
1162 | eDcutoff = settingsPtr->mode("ExtraDimensionsUnpart:CutOffMode"); |
---|
1163 | } |
---|
1164 | |
---|
1165 | // The A(dU) or S'(n) value. |
---|
1166 | double tmpAdU = 0; |
---|
1167 | if (eDgraviton) { |
---|
1168 | tmpAdU = 2 * M_PI * sqrt( pow(M_PI, double(eDnGrav)) ) |
---|
1169 | / GammaReal(0.5 * eDnGrav); |
---|
1170 | if (eDspin == 0) { // Scalar graviton |
---|
1171 | tmpAdU *= sqrt( pow(2., double(eDnGrav)) ); |
---|
1172 | eDcf *= eDcf; |
---|
1173 | } |
---|
1174 | } else { |
---|
1175 | tmpAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
1176 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
1177 | } |
---|
1178 | |
---|
1179 | // Cross section related constants |
---|
1180 | // and ME dependent powers of lambda / LambdaU. |
---|
1181 | double tmpExp = eDdU - 2; |
---|
1182 | double tmpLS = pow2(eDLambdaU); |
---|
1183 | eDconstantTerm = tmpAdU / (2 * 16 * pow2(M_PI) * tmpLS * pow(tmpLS,tmpExp)); |
---|
1184 | if (eDgraviton) { |
---|
1185 | eDconstantTerm /= tmpLS; |
---|
1186 | } else if (eDspin == 0) { |
---|
1187 | eDconstantTerm *= pow2(eDlambda) / tmpLS; |
---|
1188 | } else { |
---|
1189 | eDconstantTerm = 0; |
---|
1190 | infoPtr->errorMsg("Error in Sigma2gg2LEDUnparticleg::initProc: " |
---|
1191 | "Incorrect spin value (turn process off)!"); |
---|
1192 | } |
---|
1193 | |
---|
1194 | } |
---|
1195 | |
---|
1196 | //-------------------------------------------------------------------------- |
---|
1197 | |
---|
1198 | void Sigma2gg2LEDUnparticleg::sigmaKin() { |
---|
1199 | |
---|
1200 | // Set graviton mass. |
---|
1201 | mG = m3; |
---|
1202 | mGS = mG*mG; |
---|
1203 | |
---|
1204 | // Set mandelstam variables and ME expressions. |
---|
1205 | if (eDgraviton) { |
---|
1206 | |
---|
1207 | double A0 = 1/sH; |
---|
1208 | if (eDspin == 0) { // Scalar graviton |
---|
1209 | double tmpTerm1 = uH + tH; |
---|
1210 | double tmpTerm2 = uH + sH; |
---|
1211 | double tmpTerm3 = tH + sH; |
---|
1212 | double T0 = pow(tmpTerm1,4) + pow(tmpTerm2,4) + pow(tmpTerm3,4) |
---|
1213 | + 12. * sH * tH * uH * mGS; |
---|
1214 | eDsigma0 = eDcf * A0 * T0 / (sH2 * tH * uH); |
---|
1215 | } else { |
---|
1216 | double xH = tH/sH; |
---|
1217 | double yH = mGS/sH; |
---|
1218 | double xHS = pow2(xH); |
---|
1219 | double yHS = pow2(yH); |
---|
1220 | double xHC = pow(xH,3); |
---|
1221 | double yHC = pow(yH,3); |
---|
1222 | double xHQ = pow(xH,4); |
---|
1223 | double yHQ = pow(yH,4); |
---|
1224 | |
---|
1225 | double T0 = 1/(xH*(yH-1-xH)); |
---|
1226 | double T1 = 1 + 2*xH + 3*xHS + 2*xHC + xHQ; |
---|
1227 | double T2 = -2*yH*(1 + xHC); |
---|
1228 | double T3 = 3*yHS*(1 + xHS); |
---|
1229 | double T4 = -2*yHC*(1 + xH); |
---|
1230 | double T5 = yHQ; |
---|
1231 | |
---|
1232 | eDsigma0 = A0 * T0 *( T1 + T2 + T3 + T4 + T5 ); |
---|
1233 | } |
---|
1234 | |
---|
1235 | } else if (eDspin == 0) { |
---|
1236 | |
---|
1237 | double A0 = 1/pow2(sH); |
---|
1238 | double sHQ = pow(sH,4); |
---|
1239 | double tHQ = pow(tH,4); |
---|
1240 | double uHQ = pow(uH,4); |
---|
1241 | |
---|
1242 | eDsigma0 = A0 * (pow(mGS,4) + sHQ + tHQ + uHQ) / (sH * tH * uH); |
---|
1243 | |
---|
1244 | } |
---|
1245 | |
---|
1246 | // Mass measure, (m^2)^(d-2). |
---|
1247 | double tmpExp = eDdU - 2; |
---|
1248 | eDsigma0 *= pow(mGS, tmpExp); |
---|
1249 | |
---|
1250 | // Constants. |
---|
1251 | eDsigma0 *= eDconstantTerm; |
---|
1252 | |
---|
1253 | } |
---|
1254 | |
---|
1255 | //-------------------------------------------------------------------------- |
---|
1256 | |
---|
1257 | double Sigma2gg2LEDUnparticleg::sigmaHat() { |
---|
1258 | |
---|
1259 | // Mass spectrum weighting. |
---|
1260 | double sigma = eDsigma0 / runBW3; |
---|
1261 | |
---|
1262 | // SM couplings... |
---|
1263 | if (eDgraviton) { |
---|
1264 | sigma *= 16 * M_PI * alpS * 3 / 16; |
---|
1265 | } else if (eDspin == 0) { |
---|
1266 | sigma *= 6 * M_PI * alpS; |
---|
1267 | } |
---|
1268 | |
---|
1269 | // Truncate sH region or use form factor. |
---|
1270 | // Form factor uses either pythia8 renormScale2 |
---|
1271 | // or E_jet in cms. |
---|
1272 | if (eDcutoff == 1) { |
---|
1273 | if (sH > pow2(eDLambdaU) ) { sigma *= pow(eDLambdaU,4)/pow2(sH); } |
---|
1274 | } else if ( (eDgraviton && (eDspin == 2)) |
---|
1275 | && ((eDcutoff == 2) || (eDcutoff == 3)) ) { |
---|
1276 | double tmPmu = sqrt(Q2RenSave); |
---|
1277 | if (eDcutoff == 3) tmPmu = (sH + s4 - s3) / (2 * mH); |
---|
1278 | double tmPformfact = tmPmu / (eDtff * eDLambdaU); |
---|
1279 | double tmPexp = double(eDnGrav) + 2; |
---|
1280 | sigma *= 1 / (1 + pow(tmPformfact, tmPexp)); |
---|
1281 | } |
---|
1282 | |
---|
1283 | return sigma; |
---|
1284 | } |
---|
1285 | |
---|
1286 | //-------------------------------------------------------------------------- |
---|
1287 | |
---|
1288 | void Sigma2gg2LEDUnparticleg::setIdColAcol() { |
---|
1289 | |
---|
1290 | // Flavours trivial. |
---|
1291 | setId( 21, 21, eDidG, 21); |
---|
1292 | |
---|
1293 | // Colour flow topologies: random choice between two mirrors. |
---|
1294 | if (rndmPtr->flat() < 0.5) setColAcol( 1, 2, 2, 3, 0, 0, 1, 3); |
---|
1295 | else setColAcol( 1, 2, 3, 1, 0, 0, 3, 2); |
---|
1296 | |
---|
1297 | } |
---|
1298 | |
---|
1299 | //========================================================================== |
---|
1300 | |
---|
1301 | // Sigma2qg2LEDUnparticleq class. |
---|
1302 | // Cross section for q g -> U/G q (real graviton emission in |
---|
1303 | // large extra dimensions or unparticle emission). |
---|
1304 | |
---|
1305 | //-------------------------------------------------------------------------- |
---|
1306 | |
---|
1307 | void Sigma2qg2LEDUnparticleq::initProc() { |
---|
1308 | |
---|
1309 | // Init model parameters. |
---|
1310 | eDidG = 5000039; |
---|
1311 | if (eDgraviton) { |
---|
1312 | eDspin = (settingsPtr->flag("ExtraDimensionsLED:GravScalar")) ? 0 : 2; |
---|
1313 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
1314 | eDdU = 0.5 * eDnGrav + 1; |
---|
1315 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
1316 | eDlambda = 1; |
---|
1317 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
1318 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
1319 | eDgf = settingsPtr->parm("ExtraDimensionsLED:g"); |
---|
1320 | eDcf = settingsPtr->parm("ExtraDimensionsLED:c"); |
---|
1321 | } else { |
---|
1322 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
1323 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
1324 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
1325 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
1326 | eDcutoff = settingsPtr->mode("ExtraDimensionsUnpart:CutOffMode"); |
---|
1327 | } |
---|
1328 | |
---|
1329 | // The A(dU) or S'(n) value. |
---|
1330 | double tmpAdU = 0; |
---|
1331 | if (eDgraviton) { |
---|
1332 | tmpAdU = 2 * M_PI * sqrt( pow(M_PI, double(eDnGrav)) ) |
---|
1333 | / GammaReal(0.5 * eDnGrav); |
---|
1334 | // Scalar graviton |
---|
1335 | if (eDspin == 0) { |
---|
1336 | tmpAdU *= 2. * sqrt( pow(2., double(eDnGrav)) ); |
---|
1337 | eDcf *= 4. * eDcf / pow2(eDLambdaU); |
---|
1338 | double tmpExp = 2. * double(eDnGrav) / (double(eDnGrav) + 2.); |
---|
1339 | eDgf *= eDgf / pow(2. * M_PI, tmpExp); |
---|
1340 | } |
---|
1341 | } else { |
---|
1342 | tmpAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
1343 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
1344 | } |
---|
1345 | |
---|
1346 | // Cross section related constants |
---|
1347 | // and ME dependent powers of lambda / LambdaU. |
---|
1348 | double tmpExp = eDdU - 2; |
---|
1349 | double tmpLS = pow2(eDLambdaU); |
---|
1350 | eDconstantTerm = tmpAdU / (2 * 16 * pow2(M_PI) * tmpLS * pow(tmpLS,tmpExp)); |
---|
1351 | if (eDgraviton && (eDspin == 2)) { |
---|
1352 | eDconstantTerm /= tmpLS; |
---|
1353 | } else if (eDspin == 1) { |
---|
1354 | eDconstantTerm *= pow2(eDlambda); |
---|
1355 | } else if (eDspin == 0) { |
---|
1356 | eDconstantTerm *= pow2(eDlambda); |
---|
1357 | } else { |
---|
1358 | eDconstantTerm = 0; |
---|
1359 | infoPtr->errorMsg("Error in Sigma2qg2LEDUnparticleq::initProc: " |
---|
1360 | "Incorrect spin value (turn process off)!"); |
---|
1361 | } |
---|
1362 | |
---|
1363 | |
---|
1364 | } |
---|
1365 | |
---|
1366 | //-------------------------------------------------------------------------- |
---|
1367 | |
---|
1368 | void Sigma2qg2LEDUnparticleq::sigmaKin() { |
---|
1369 | |
---|
1370 | // Set graviton mass. |
---|
1371 | mG = m3; |
---|
1372 | mGS = mG*mG; |
---|
1373 | |
---|
1374 | // Set mandelstam variables and ME expressions. |
---|
1375 | if (eDgraviton) { |
---|
1376 | |
---|
1377 | double A0 = 1/sH; |
---|
1378 | // Scalar graviton |
---|
1379 | if (eDspin == 0) { |
---|
1380 | A0 /= sH; |
---|
1381 | double T0 = -(uH2 + pow2(mGS)) / (sH * tH); |
---|
1382 | double T1 = -(tH2 + sH2)/ uH; |
---|
1383 | eDsigma0 = A0 * (eDgf * T0 + eDcf * T1); |
---|
1384 | } else { |
---|
1385 | double xH = tH/sH; |
---|
1386 | double yH = mGS/sH; |
---|
1387 | double x2H = xH/(yH - 1 - xH); |
---|
1388 | double y2H = yH/(yH - 1 - xH); |
---|
1389 | double x2HS = pow2(x2H); |
---|
1390 | double y2HS = pow2(y2H); |
---|
1391 | double x2HC = pow(x2H,3); |
---|
1392 | double y2HC = pow(y2H,3); |
---|
1393 | |
---|
1394 | double T0 = -(yH - 1 - xH); |
---|
1395 | double T20 = 1/(x2H*(y2H-1-x2H)); |
---|
1396 | double T21 = -4*x2H*(1 + x2H)*(1 + 2*x2H + 2*x2HS); |
---|
1397 | double T22 = y2H*(1 + 6*x2H + 18*x2HS + 16*x2HC); |
---|
1398 | double T23 = -6*y2HS*x2H*(1+2*x2H); |
---|
1399 | double T24 = y2HC*(1 + 4*x2H); |
---|
1400 | |
---|
1401 | eDsigma0 = A0 * T0 * T20 * ( T21 + T22 + T23 + T24 ); |
---|
1402 | } |
---|
1403 | |
---|
1404 | } else if (eDspin == 1) { |
---|
1405 | |
---|
1406 | double A0 = 1/pow2(sH); |
---|
1407 | double tmpTerm1 = tH - mGS; |
---|
1408 | double tmpTerm2 = sH - mGS; |
---|
1409 | |
---|
1410 | eDsigma0 = A0 * (pow2(tmpTerm1) + pow2(tmpTerm2)) / (sH*tH); |
---|
1411 | |
---|
1412 | } else if (eDspin == 0) { |
---|
1413 | |
---|
1414 | double A0 = 1/pow2(sH); |
---|
1415 | // Sign correction by Tom |
---|
1416 | eDsigma0 = A0 * (pow2(tH) + pow2(mGS)) / (sH*uH); |
---|
1417 | |
---|
1418 | } |
---|
1419 | |
---|
1420 | // Mass measure, (m^2)^(d-2). |
---|
1421 | double tmpExp = eDdU - 2; |
---|
1422 | eDsigma0 *= pow(mGS, tmpExp); |
---|
1423 | |
---|
1424 | // Constants. |
---|
1425 | eDsigma0 *= eDconstantTerm; |
---|
1426 | |
---|
1427 | } |
---|
1428 | |
---|
1429 | //-------------------------------------------------------------------------- |
---|
1430 | |
---|
1431 | double Sigma2qg2LEDUnparticleq::sigmaHat() { |
---|
1432 | |
---|
1433 | // Mass spactrum weighting. |
---|
1434 | double sigma = eDsigma0 /runBW3; |
---|
1435 | |
---|
1436 | // SM couplings... |
---|
1437 | if (eDgraviton) { |
---|
1438 | sigma *= 16 * M_PI * alpS / 96; |
---|
1439 | } else if (eDspin == 1) { |
---|
1440 | sigma *= - 4 * M_PI * alpS / 3; |
---|
1441 | } else if (eDspin == 0) { |
---|
1442 | sigma *= - 2 * M_PI * alpS / 3; |
---|
1443 | } |
---|
1444 | |
---|
1445 | // Truncate sH region or use form factor. |
---|
1446 | // Form factor uses either pythia8 renormScale2 |
---|
1447 | // or E_jet in cms. |
---|
1448 | if (eDcutoff == 1) { |
---|
1449 | if (sH > pow2(eDLambdaU) ) { sigma *= pow(eDLambdaU,4)/pow2(sH); } |
---|
1450 | } else if ( (eDgraviton && (eDspin == 2)) |
---|
1451 | && ((eDcutoff == 2) || (eDcutoff == 3)) ) { |
---|
1452 | double tmPmu = sqrt(Q2RenSave); |
---|
1453 | if (eDcutoff == 3) tmPmu = (sH + s4 - s3) / (2 * mH); |
---|
1454 | double tmPformfact = tmPmu / (eDtff * eDLambdaU); |
---|
1455 | double tmPexp = double(eDnGrav) + 2; |
---|
1456 | sigma *= 1 / (1 + pow(tmPformfact, tmPexp)); |
---|
1457 | } |
---|
1458 | |
---|
1459 | return sigma; |
---|
1460 | } |
---|
1461 | |
---|
1462 | //-------------------------------------------------------------------------- |
---|
1463 | |
---|
1464 | void Sigma2qg2LEDUnparticleq::setIdColAcol() { |
---|
1465 | |
---|
1466 | // Flavour set up for q g -> G* q. |
---|
1467 | int idq = (id2 == 21) ? id1 : id2; |
---|
1468 | setId( id1, id2, eDidG, idq); |
---|
1469 | |
---|
1470 | // tH defined between f and f': must swap tHat <-> uHat if q g in. |
---|
1471 | swapTU = (id2 == 21); |
---|
1472 | |
---|
1473 | // Colour flow topologies. Swap when antiquarks. |
---|
1474 | if (id2 == 21) setColAcol( 1, 0, 2, 1, 0, 0, 2, 0); |
---|
1475 | else setColAcol( 2, 1, 1, 0, 0, 0, 2, 0); |
---|
1476 | if (idq < 0) swapColAcol(); |
---|
1477 | |
---|
1478 | } |
---|
1479 | |
---|
1480 | //========================================================================== |
---|
1481 | |
---|
1482 | // Sigma2qqbar2LEDUnparticleg class. |
---|
1483 | // Cross section for q qbar -> U/G g (real graviton emission in |
---|
1484 | // large extra dimensions or unparticle emission). |
---|
1485 | |
---|
1486 | //-------------------------------------------------------------------------- |
---|
1487 | |
---|
1488 | void Sigma2qqbar2LEDUnparticleg::initProc() { |
---|
1489 | |
---|
1490 | // Init model parameters. |
---|
1491 | eDidG = 5000039; |
---|
1492 | if (eDgraviton) { |
---|
1493 | eDspin = (settingsPtr->flag("ExtraDimensionsLED:GravScalar")) ? 0 : 2; |
---|
1494 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
1495 | eDdU = 0.5 * eDnGrav + 1; |
---|
1496 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
1497 | eDlambda = 1; |
---|
1498 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
1499 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
1500 | eDgf = settingsPtr->parm("ExtraDimensionsLED:g"); |
---|
1501 | eDcf = settingsPtr->parm("ExtraDimensionsLED:c"); |
---|
1502 | } else { |
---|
1503 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
1504 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
1505 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
1506 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
1507 | eDcutoff = settingsPtr->mode("ExtraDimensionsUnpart:CutOffMode"); |
---|
1508 | } |
---|
1509 | |
---|
1510 | // The A(dU) or S'(n) value. |
---|
1511 | double tmpAdU = 0; |
---|
1512 | if (eDgraviton) { |
---|
1513 | tmpAdU = 2 * M_PI * sqrt( pow(M_PI, double(eDnGrav)) ) |
---|
1514 | / GammaReal(0.5 * eDnGrav); |
---|
1515 | // Scalar graviton |
---|
1516 | if (eDspin == 0) { |
---|
1517 | tmpAdU *= 2. * sqrt( pow(2., double(eDnGrav)) ); |
---|
1518 | eDcf *= 4. * eDcf / pow2(eDLambdaU); |
---|
1519 | double tmpExp = 2. * double(eDnGrav) / (double(eDnGrav) + 2.); |
---|
1520 | eDgf *= eDgf / pow(2. * M_PI, tmpExp); |
---|
1521 | } |
---|
1522 | } else { |
---|
1523 | tmpAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
1524 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
1525 | } |
---|
1526 | |
---|
1527 | // Cross section related constants |
---|
1528 | // and ME dependent powers of lambda / LambdaU. |
---|
1529 | double tmpExp = eDdU - 2; |
---|
1530 | double tmpLS = pow2(eDLambdaU); |
---|
1531 | eDconstantTerm = tmpAdU / (2 * 16 * pow2(M_PI) * tmpLS * pow(tmpLS,tmpExp)); |
---|
1532 | if (eDgraviton && (eDspin == 2)) { |
---|
1533 | eDconstantTerm /= tmpLS; |
---|
1534 | } else if (eDspin == 1) { |
---|
1535 | eDconstantTerm *= pow2(eDlambda); |
---|
1536 | } else if (eDspin == 0) { |
---|
1537 | eDconstantTerm *= pow2(eDlambda); |
---|
1538 | } else { |
---|
1539 | eDconstantTerm = 0; |
---|
1540 | infoPtr->errorMsg("Error in Sigma2qqbar2LEDUnparticleg::initProc: " |
---|
1541 | "Incorrect spin value (turn process off)!"); |
---|
1542 | } |
---|
1543 | |
---|
1544 | } |
---|
1545 | |
---|
1546 | //-------------------------------------------------------------------------- |
---|
1547 | |
---|
1548 | void Sigma2qqbar2LEDUnparticleg::sigmaKin() { |
---|
1549 | |
---|
1550 | // Set graviton mass. |
---|
1551 | mG = m3; |
---|
1552 | mGS = mG*mG; |
---|
1553 | |
---|
1554 | // Set mandelstam variables and ME expressions. |
---|
1555 | if (eDgraviton) { |
---|
1556 | |
---|
1557 | double A0 = 1/sH; |
---|
1558 | // Scalar graviton |
---|
1559 | if (eDspin == 0) { |
---|
1560 | A0 /= sH; |
---|
1561 | double tmpTerm1 = uH + tH; |
---|
1562 | double T0 = (2. * mGS * sH + pow2(tmpTerm1)) / (uH * tH); |
---|
1563 | double T1 = (tH2 + uH2) / sH; |
---|
1564 | eDsigma0 = A0 * (eDgf * T0 + eDcf * T1); |
---|
1565 | } else { |
---|
1566 | double xH = tH/sH; |
---|
1567 | double yH = mGS/sH; |
---|
1568 | double xHS = pow2(xH); |
---|
1569 | double yHS = pow2(yH); |
---|
1570 | double xHC = pow(xH,3); |
---|
1571 | double yHC = pow(yH,3); |
---|
1572 | |
---|
1573 | double T0 = 1/(xH*(yH-1-xH)); |
---|
1574 | double T1 = -4*xH*(1 + xH)*(1 + 2*xH + 2*xHS); |
---|
1575 | double T2 = yH*(1 + 6*xH + 18*xHS + 16*xHC); |
---|
1576 | double T3 = -6*yHS*xH*(1+2*xH); |
---|
1577 | double T4 = yHC*(1 + 4*xH); |
---|
1578 | |
---|
1579 | eDsigma0 = A0 * T0 *( T1 + T2 + T3 + T4 ); |
---|
1580 | } |
---|
1581 | |
---|
1582 | } else if (eDspin == 1) { |
---|
1583 | |
---|
1584 | double A0 = 1/pow2(sH); |
---|
1585 | double tmpTerm1 = tH - mGS; |
---|
1586 | double tmpTerm2 = uH - mGS; |
---|
1587 | |
---|
1588 | eDsigma0 = A0 * (pow2(tmpTerm1) + pow2(tmpTerm2)) / (tH * uH); |
---|
1589 | |
---|
1590 | } else if (eDspin == 0) { |
---|
1591 | |
---|
1592 | double A0 = 1/pow2(sH); |
---|
1593 | |
---|
1594 | eDsigma0 = A0 * (pow2(sH) - pow2(mGS)) / (tH * uH); |
---|
1595 | |
---|
1596 | } |
---|
1597 | |
---|
1598 | // Mass measure, (m^2)^(d-2). |
---|
1599 | double tmpExp = eDdU - 2; |
---|
1600 | eDsigma0 *= pow(mGS, tmpExp); |
---|
1601 | |
---|
1602 | // Constants. |
---|
1603 | eDsigma0 *= eDconstantTerm; |
---|
1604 | |
---|
1605 | } |
---|
1606 | |
---|
1607 | //-------------------------------------------------------------------------- |
---|
1608 | |
---|
1609 | double Sigma2qqbar2LEDUnparticleg::sigmaHat() { |
---|
1610 | |
---|
1611 | // Mass spactrum weighting. |
---|
1612 | double sigma = eDsigma0 /runBW3; |
---|
1613 | |
---|
1614 | // SM couplings... |
---|
1615 | if (eDgraviton) { |
---|
1616 | sigma *= 16 * M_PI * alpS / 36; |
---|
1617 | } else if (eDspin == 1) { |
---|
1618 | sigma *= 4 * M_PI * 8 * alpS / 9; |
---|
1619 | } else if (eDspin == 0) { |
---|
1620 | sigma *= 4 * M_PI * 4 * alpS / 9; |
---|
1621 | } |
---|
1622 | |
---|
1623 | // Truncate sH region or use form factor. |
---|
1624 | // Form factor uses either pythia8 renormScale2 |
---|
1625 | // or E_jet in cms. |
---|
1626 | if (eDcutoff == 1) { |
---|
1627 | if (sH > pow2(eDLambdaU) ) { sigma *= pow(eDLambdaU,4)/pow2(sH); } |
---|
1628 | } else if ( (eDgraviton && (eDspin == 2)) |
---|
1629 | && ((eDcutoff == 2) || (eDcutoff == 3)) ) { |
---|
1630 | double tmPmu = sqrt(Q2RenSave); |
---|
1631 | if (eDcutoff == 3) tmPmu = (sH + s4 - s3) / (2 * mH); |
---|
1632 | double tmPformfact = tmPmu / (eDtff * eDLambdaU); |
---|
1633 | double tmPexp = double(eDnGrav) + 2; |
---|
1634 | sigma *= 1 / (1 + pow(tmPformfact, tmPexp)); |
---|
1635 | } |
---|
1636 | |
---|
1637 | return sigma; |
---|
1638 | } |
---|
1639 | |
---|
1640 | //-------------------------------------------------------------------------- |
---|
1641 | |
---|
1642 | void Sigma2qqbar2LEDUnparticleg::setIdColAcol() { |
---|
1643 | |
---|
1644 | // Flavours trivial. |
---|
1645 | setId( id1, id2, eDidG, 21); |
---|
1646 | |
---|
1647 | // Colour flow topologies. Swap when antiquarks. |
---|
1648 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 2, 0, 0, 1, 2); |
---|
1649 | if (id1 < 0) swapColAcol(); |
---|
1650 | |
---|
1651 | } |
---|
1652 | |
---|
1653 | //========================================================================== |
---|
1654 | |
---|
1655 | // Sigma2ffbar2LEDUnparticleZ class. |
---|
1656 | // Cross section for f fbar -> U/G Z (real LED graviton or unparticle |
---|
1657 | // emission). |
---|
1658 | |
---|
1659 | //-------------------------------------------------------------------------- |
---|
1660 | |
---|
1661 | // Constants: could be changed here if desired, but normally should not. |
---|
1662 | // These are of technical nature, as described for each. |
---|
1663 | |
---|
1664 | // FIXRATIO: |
---|
1665 | // Ratio between the two possible coupling constants of the spin-2 ME. |
---|
1666 | // A value different from one give rise to an IR divergence which makes |
---|
1667 | // the event generation very slow, so this values is fixed to 1 until |
---|
1668 | // investigated further. |
---|
1669 | const double Sigma2ffbar2LEDUnparticleZ::FIXRATIO = 1.; |
---|
1670 | |
---|
1671 | //-------------------------------------------------------------------------- |
---|
1672 | |
---|
1673 | void Sigma2ffbar2LEDUnparticleZ::initProc() { |
---|
1674 | |
---|
1675 | // Init model parameters. |
---|
1676 | eDidG = 5000039; |
---|
1677 | if (eDgraviton) { |
---|
1678 | eDspin = 2; |
---|
1679 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
1680 | eDdU = 0.5 * eDnGrav + 1; |
---|
1681 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
1682 | eDlambda = 1; |
---|
1683 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
1684 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
1685 | } else { |
---|
1686 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
1687 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
1688 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
1689 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
1690 | eDratio = FIXRATIO; |
---|
1691 | // = settingsPtr->parm("ExtraDimensionsUnpart:ratio"); |
---|
1692 | eDcutoff = settingsPtr->mode("ExtraDimensionsUnpart:CutOffMode"); |
---|
1693 | } |
---|
1694 | |
---|
1695 | // Store Z0 mass and width for propagator. |
---|
1696 | mZ = particleDataPtr->m0(23); |
---|
1697 | widZ = particleDataPtr->mWidth(23); |
---|
1698 | mZS = mZ*mZ; |
---|
1699 | mwZS = pow2(mZ * widZ); |
---|
1700 | |
---|
1701 | // Init spin-2 parameters |
---|
1702 | if ( eDspin != 2 ){ |
---|
1703 | eDgraviton = false; |
---|
1704 | eDlambdaPrime = 0; |
---|
1705 | } else if (eDgraviton) { |
---|
1706 | eDlambda = 1; |
---|
1707 | eDratio = 1; |
---|
1708 | eDlambdaPrime = eDlambda; |
---|
1709 | } else { |
---|
1710 | eDlambdaPrime = eDratio * eDlambda; |
---|
1711 | } |
---|
1712 | |
---|
1713 | // The A(dU) or S'(n) value |
---|
1714 | double tmpAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
1715 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
1716 | |
---|
1717 | if (eDgraviton) { |
---|
1718 | tmpAdU = 2 * M_PI * sqrt( pow(M_PI, double(eDnGrav)) ) |
---|
1719 | / GammaReal(0.5 * eDnGrav); |
---|
1720 | } |
---|
1721 | |
---|
1722 | // Standard 2 to 2 cross section related constants |
---|
1723 | double tmpTerm1 = 1/(2 * 16 * pow2(M_PI)); |
---|
1724 | double tmpLS = pow2(eDLambdaU); |
---|
1725 | |
---|
1726 | // Spin dependent constants from ME. |
---|
1727 | double tmpTerm2 = 0; |
---|
1728 | if ( eDspin == 0 ) { |
---|
1729 | tmpTerm2 = 2 * pow2(eDlambda); |
---|
1730 | } else if (eDspin == 1) { |
---|
1731 | tmpTerm2 = 4 * pow2(eDlambda); |
---|
1732 | } else if (eDspin == 2) { |
---|
1733 | tmpTerm2 = pow2(eDlambda)/(4 * 3 * tmpLS); |
---|
1734 | } |
---|
1735 | |
---|
1736 | // Unparticle phase space related |
---|
1737 | double tmpExp2 = eDdU - 2; |
---|
1738 | double tmpTerm3 = tmpAdU / (tmpLS * pow(tmpLS, tmpExp2)); |
---|
1739 | |
---|
1740 | // All in total |
---|
1741 | eDconstantTerm = tmpTerm1 * tmpTerm2 * tmpTerm3; |
---|
1742 | |
---|
1743 | } |
---|
1744 | |
---|
1745 | //-------------------------------------------------------------------------- |
---|
1746 | |
---|
1747 | void Sigma2ffbar2LEDUnparticleZ::sigmaKin() { |
---|
1748 | |
---|
1749 | // Set graviton mass and some powers of mandelstam variables |
---|
1750 | mU = m3; |
---|
1751 | mUS = mU*mU; |
---|
1752 | |
---|
1753 | sHS = pow2(sH); |
---|
1754 | tHS = pow2(tH); |
---|
1755 | uHS = pow2(uH); |
---|
1756 | tHC = pow(tH,3); |
---|
1757 | uHC = pow(uH,3); |
---|
1758 | tHQ = pow(tH,4); |
---|
1759 | uHQ = pow(uH,4); |
---|
1760 | tHuH = tH+uH; |
---|
1761 | |
---|
1762 | // Evaluate (m**2, t, u) part of differential cross section. |
---|
1763 | // Extra 1/sHS comes from standard 2 to 2 cross section |
---|
1764 | // phase space factors. |
---|
1765 | |
---|
1766 | if ( eDspin == 0 ) { |
---|
1767 | |
---|
1768 | double A0 = 1/sHS; |
---|
1769 | double T1 = - sH/tH - sH/uH; |
---|
1770 | double T2 = - (1 - mZS/tH)*(1 - mUS/tH); |
---|
1771 | double T3 = - (1 - mZS/uH)*(1 - mUS/uH); |
---|
1772 | double T4 = 2*(1 - mUS/tH)*(1 - mUS/uH); |
---|
1773 | |
---|
1774 | eDsigma0 = A0 * ( T1 + T2 + T3 + T4); |
---|
1775 | |
---|
1776 | } else if ( eDspin == 1 ) { |
---|
1777 | |
---|
1778 | double A0 = 1/sHS; |
---|
1779 | double T1 = 0.5 * (tH/uH + uH/tH); |
---|
1780 | double T2 = pow2(mZS + mUS)/(tH * uH); |
---|
1781 | double T3 = - 0.5 * mUS * (mZS/tHS + mZS/uHS) ; |
---|
1782 | double T4 = - (mZS+mUS)*(1/tH + 1/uH); |
---|
1783 | |
---|
1784 | eDsigma0 = A0 * ( T1 + T2 + T3 + T4 ); |
---|
1785 | |
---|
1786 | } else if ( eDspin == 2 ) { |
---|
1787 | |
---|
1788 | double A0 = 1 / ( sHS * uHS * tHS * pow2(sH-mZS) ); |
---|
1789 | double F0 = 2*tHS*uHS*( 16*pow(mZS,3) + mUS*(7*tHS + 12*tH*uH + 7*uHS) |
---|
1790 | - 3*(3*tHC + 11*tHS*uH + 11*tH*uHS + 3*uHC) |
---|
1791 | + 6*pow(mZS,2)*(7*mUS - 2*tHuH) + mZS*(14*pow(mUS,2) |
---|
1792 | - 15*tHS - 44*tH*uH - 15*uHS + 2*mUS*tHuH) ); |
---|
1793 | double F2 = 2*tHS*uHS*tHuH*( -8*pow(mZS,2)*tHuH |
---|
1794 | + 4*mZS*(tHS + 3*tH*uH + uHS) |
---|
1795 | + 3*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) ); |
---|
1796 | double F4 = -2*tHS*uHS*pow(tHuH,3)*(tHS + uHS - mZS*tHuH); |
---|
1797 | |
---|
1798 | double G0 = 4*tH*uH*( 6*pow(mZS,3)*(mUS - tH - uH)*tHuH |
---|
1799 | + pow(mZS,2)*( 9*tHC + 7*tHS*uH + 7*tH*uHS + 9*uHC |
---|
1800 | + 15*pow2(mUS)*tHuH - 2*mUS*(12*tHS + 19*tH*uH + 12*uHS) ) |
---|
1801 | + tH*uH*( 6*pow(mUS,3) - 9*pow(mUS,2)*tHuH - mUS*(tHS |
---|
1802 | + 12*tH*uH + uHS) + 6*(tHC + 6*tHS*uH + 6*tH*uHS + uHC) ) |
---|
1803 | + mZS*(-3*tHQ + 25*tHC*uH + 58*tHS*uHS + 25*tH*uHC |
---|
1804 | - 3*uHQ + 6*pow(mUS,3)*tHuH |
---|
1805 | - pow(mUS,2)*(15*tHS + 2*tH*uH + 15*uHS) + 2*mUS*(6*tHC |
---|
1806 | - 11*tHS*uH - 11*tH*uHS + 6*uHC)) ); |
---|
1807 | double G2 = -4*tHS*uHS*tHuH*( -10*pow2(mZS)*tHuH + 2*mZS*(3*tHS |
---|
1808 | + 7*tH*uH + 3*uHS) + 3*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) ); |
---|
1809 | double G4 = -2*F4; |
---|
1810 | |
---|
1811 | double H0 = 24*pow(mZS,3)*tH*uH*pow2(-mUS + tHuH) |
---|
1812 | - 6*pow(mZS,2)*tH*uH*( -9*pow(mUS,3) + 24*pow(mUS,2)*tHuH |
---|
1813 | - mUS*(21*tHS + 38*tH*uH + 21*uHS) |
---|
1814 | + 2*(3*tHC + 5*tHS*uH + 5*tH*uHS + 3*uHC) ) |
---|
1815 | - mZS*( 3*pow(mUS,4)*(tHS - 12*tH*uH + uHS) |
---|
1816 | - 2*tH*uH*pow2(tHuH)*(6*tHS - 29*tH*uH + 6*uHS) |
---|
1817 | - 6*pow(mUS,3)*(tHC - 16*tHS*uH - 16*tH*uHS + uHC) |
---|
1818 | + 54*mUS*tH*uH*(tHC + tHS*uH + tH*uHS + uHC) |
---|
1819 | + pow2(mUS)*(3*tHQ - 102*tHC*uH - 166*tHS*uHS |
---|
1820 | - 102*tH*uHC + 3*uHQ) ) |
---|
1821 | + tH*uH*( 6*pow(mUS,5) - 18*pow(mUS,4)*tHuH |
---|
1822 | - 12*pow(mUS,2)*pow(tHuH,3) |
---|
1823 | + 3*pow(mUS,3)*(7*tHS + 12*tH*uH + 7*uHS) |
---|
1824 | - 18*tH*uH*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) |
---|
1825 | + mUS*(3*tHQ + 32*tHC*uH + 78*tHS*uHS + 32*tH*uHC + 3*uHQ) ); |
---|
1826 | double H2 = 2*tHS*uHS*pow2(tHuH)*( -12*pow2(mZS) + 8*mZS*tHuH |
---|
1827 | + 3*(tHS + 4*tH*uH + uHS) ); |
---|
1828 | double H4 = F4; |
---|
1829 | |
---|
1830 | eDsigma0 = A0*( F0 + 1/mUS*F2 + 1/pow2(mUS)*F4 |
---|
1831 | + eDratio*(G0 + 1/mUS*G2 + 1/pow2(mUS)*G4) |
---|
1832 | + pow2(eDratio)*(H0 + 1/mUS*H2 + 1/pow2(mUS)*H4) ); |
---|
1833 | |
---|
1834 | } else { |
---|
1835 | |
---|
1836 | eDsigma0 = 0; |
---|
1837 | |
---|
1838 | } |
---|
1839 | |
---|
1840 | } |
---|
1841 | |
---|
1842 | //-------------------------------------------------------------------------- |
---|
1843 | |
---|
1844 | double Sigma2ffbar2LEDUnparticleZ::sigmaHat() { |
---|
1845 | |
---|
1846 | // Electroweak couplings. |
---|
1847 | int idAbs = abs(id1); |
---|
1848 | // Note: 1/2 * (g_L^2 + g_R^2) = (g_v^2 + g_a^2) |
---|
1849 | double facEWS = 4 * M_PI * alpEM |
---|
1850 | / (couplingsPtr->sin2thetaW() * couplingsPtr->cos2thetaW()) |
---|
1851 | * ( 0.25 * 0.25 * couplingsPtr->vf2af2(idAbs) ); |
---|
1852 | |
---|
1853 | // Mass Spectrum, (m^2)^(d-2) |
---|
1854 | double tmpExp = eDdU - 2; |
---|
1855 | double facSpect = pow(mUS, tmpExp); |
---|
1856 | |
---|
1857 | // Total cross section |
---|
1858 | double sigma = eDconstantTerm * facEWS * facSpect * eDsigma0; |
---|
1859 | |
---|
1860 | // If f fbar are quarks (1/N_c) |
---|
1861 | if (idAbs < 9) sigma /= 3.; |
---|
1862 | |
---|
1863 | // Related to mass spactrum weighting. |
---|
1864 | sigma /= runBW3; |
---|
1865 | |
---|
1866 | // Truncate sH region or use form factor. |
---|
1867 | // Form factor uses either pythia8 renormScale2 |
---|
1868 | // or E_jet in cms. |
---|
1869 | if (eDcutoff == 1) { |
---|
1870 | if (sH > pow2(eDLambdaU) ) { sigma *= pow(eDLambdaU,4)/pow2(sH); } |
---|
1871 | } else if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
1872 | double tmPmu = sqrt(Q2RenSave); |
---|
1873 | if (eDcutoff == 3) tmPmu = (sH + s4 - s3) / (2 * mH); |
---|
1874 | double tmPformfact = tmPmu / (eDtff * eDLambdaU); |
---|
1875 | double tmPexp = double(eDnGrav) + 2; |
---|
1876 | sigma *= 1 / (1 + pow(tmPformfact, tmPexp)); |
---|
1877 | } |
---|
1878 | |
---|
1879 | return sigma; |
---|
1880 | |
---|
1881 | } |
---|
1882 | |
---|
1883 | //-------------------------------------------------------------------------- |
---|
1884 | |
---|
1885 | void Sigma2ffbar2LEDUnparticleZ::setIdColAcol() { |
---|
1886 | |
---|
1887 | // Flavours trivial. |
---|
1888 | setId( id1, id2, eDidG, 23); |
---|
1889 | |
---|
1890 | // Colour flow topologies. Swap when antiquarks. |
---|
1891 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0); |
---|
1892 | else setColAcol( 0, 0, 0, 0, 0, 0); |
---|
1893 | if (id1 < 0) swapColAcol(); |
---|
1894 | |
---|
1895 | } |
---|
1896 | |
---|
1897 | //========================================================================== |
---|
1898 | |
---|
1899 | // Sigma2ffbar2LEDUnparticlegamma class. |
---|
1900 | // Cross section for f fbar -> U/G gamma (real LED graviton or unparticle |
---|
1901 | // emission). |
---|
1902 | |
---|
1903 | //-------------------------------------------------------------------------- |
---|
1904 | |
---|
1905 | // Constants: could be changed here if desired, but normally should not. |
---|
1906 | // These are of technical nature, as described for each. |
---|
1907 | |
---|
1908 | // FIXRATIO: |
---|
1909 | // Ratio between the two possible coupling constants of the spin-2 ME. |
---|
1910 | // A value different from one give rise to an IR divergence which makes |
---|
1911 | // the event generation very slow, so this values is fixed to 1 until |
---|
1912 | // investigated further. |
---|
1913 | const double Sigma2ffbar2LEDUnparticlegamma::FIXRATIO = 1.; |
---|
1914 | |
---|
1915 | //-------------------------------------------------------------------------- |
---|
1916 | |
---|
1917 | void Sigma2ffbar2LEDUnparticlegamma::initProc() { |
---|
1918 | |
---|
1919 | // WARNING: Keep in mind that this class uses the photon limit |
---|
1920 | // of the Z+G/U ME code. This might give rise to some |
---|
1921 | // confusing things, e.g. mZ = particleDataPtr->m0(22); |
---|
1922 | |
---|
1923 | // Init model parameters. |
---|
1924 | eDidG = 5000039; |
---|
1925 | if (eDgraviton) { |
---|
1926 | eDspin = 2; |
---|
1927 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
1928 | eDdU = 0.5 * eDnGrav + 1; |
---|
1929 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
1930 | eDlambda = 1; |
---|
1931 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
1932 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
1933 | } else { |
---|
1934 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
1935 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
1936 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
1937 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
1938 | eDratio = FIXRATIO; |
---|
1939 | // = settingsPtr->parm("ExtraDimensionsUnpart:ratio"); |
---|
1940 | eDcutoff = settingsPtr->mode("ExtraDimensionsUnpart:CutOffMode"); |
---|
1941 | } |
---|
1942 | |
---|
1943 | // Store Z0 mass. |
---|
1944 | mZ = particleDataPtr->m0(22); |
---|
1945 | mZS = mZ*mZ; |
---|
1946 | |
---|
1947 | // Init spin-2 parameters |
---|
1948 | if ( eDspin != 2 ){ |
---|
1949 | eDgraviton = false; |
---|
1950 | eDlambdaPrime = 0; |
---|
1951 | } else if (eDgraviton) { |
---|
1952 | eDlambda = 1; |
---|
1953 | eDratio = 1; |
---|
1954 | eDlambdaPrime = eDlambda; |
---|
1955 | } else { |
---|
1956 | eDlambdaPrime = eDratio * eDlambda; |
---|
1957 | } |
---|
1958 | |
---|
1959 | // The A(dU) or S'(n) value |
---|
1960 | double tmpAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
1961 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
1962 | |
---|
1963 | if (eDgraviton) { |
---|
1964 | tmpAdU = 2 * M_PI * sqrt( pow(M_PI, double(eDnGrav)) ) |
---|
1965 | / GammaReal(0.5 * eDnGrav); |
---|
1966 | } |
---|
1967 | |
---|
1968 | // Standard 2 to 2 cross section related constants |
---|
1969 | double tmpTerm1 = 1/(2 * 16 * pow2(M_PI)); |
---|
1970 | double tmpLS = pow2(eDLambdaU); |
---|
1971 | |
---|
1972 | // Spin dependent constants from ME. |
---|
1973 | double tmpTerm2 = 0; |
---|
1974 | if ( eDspin == 0 ) { |
---|
1975 | tmpTerm2 = 2 * pow2(eDlambda); |
---|
1976 | } else if (eDspin == 1) { |
---|
1977 | tmpTerm2 = 4 * pow2(eDlambda); |
---|
1978 | } else if (eDspin == 2) { |
---|
1979 | tmpTerm2 = pow2(eDlambda)/(4 * 3 * tmpLS); |
---|
1980 | } |
---|
1981 | |
---|
1982 | // Unparticle phase space related |
---|
1983 | double tmpExp2 = eDdU - 2; |
---|
1984 | double tmpTerm3 = tmpAdU / (tmpLS * pow(tmpLS, tmpExp2)); |
---|
1985 | |
---|
1986 | // All in total |
---|
1987 | eDconstantTerm = tmpTerm1 * tmpTerm2 * tmpTerm3; |
---|
1988 | |
---|
1989 | } |
---|
1990 | |
---|
1991 | //-------------------------------------------------------------------------- |
---|
1992 | |
---|
1993 | void Sigma2ffbar2LEDUnparticlegamma::sigmaKin() { |
---|
1994 | |
---|
1995 | // Set graviton mass and some powers of mandelstam variables |
---|
1996 | mU = m3; |
---|
1997 | mUS = mU*mU; |
---|
1998 | |
---|
1999 | sHS = pow2(sH); |
---|
2000 | tHS = pow2(tH); |
---|
2001 | uHS = pow2(uH); |
---|
2002 | tHC = pow(tH,3); |
---|
2003 | uHC = pow(uH,3); |
---|
2004 | tHQ = pow(tH,4); |
---|
2005 | uHQ = pow(uH,4); |
---|
2006 | tHuH = tH+uH; |
---|
2007 | |
---|
2008 | // Evaluate (m**2, t, u) part of differential cross section. |
---|
2009 | // Extra 1/sHS comes from standard 2 to 2 cross section |
---|
2010 | // phase space factors. |
---|
2011 | |
---|
2012 | if ( eDspin == 0 ) { |
---|
2013 | |
---|
2014 | double A0 = 1/sHS; |
---|
2015 | double T1 = - sH/tH - sH/uH; |
---|
2016 | double T2 = - (1 - mZS/tH)*(1 - mUS/tH); |
---|
2017 | double T3 = - (1 - mZS/uH)*(1 - mUS/uH); |
---|
2018 | double T4 = 2*(1 - mUS/tH)*(1 - mUS/uH); |
---|
2019 | |
---|
2020 | eDsigma0 = A0 * ( T1 + T2 + T3 + T4); |
---|
2021 | |
---|
2022 | } else if ( eDspin == 1 ) { |
---|
2023 | |
---|
2024 | double A0 = 1/sHS; |
---|
2025 | double T1 = 0.5 * (tH/uH + uH/tH); |
---|
2026 | double T2 = pow2(mZS + mUS)/(tH * uH); |
---|
2027 | double T3 = - 0.5 * mUS * (mZS/tHS + mZS/uHS) ; |
---|
2028 | double T4 = - (mZS+mUS)*(1/tH + 1/uH); |
---|
2029 | |
---|
2030 | eDsigma0 = A0 * ( T1 + T2 + T3 + T4 ); |
---|
2031 | |
---|
2032 | } else if ( eDspin == 2 ) { |
---|
2033 | |
---|
2034 | double A0 = 1 / ( sHS * uHS * tHS * pow2(sH-mZS) ); |
---|
2035 | double F0 = 2*tHS*uHS*( 16*pow(mZS,3) + mUS*(7*tHS + 12*tH*uH + 7*uHS) |
---|
2036 | - 3*(3*tHC + 11*tHS*uH + 11*tH*uHS + 3*uHC) |
---|
2037 | + 6*pow(mZS,2)*(7*mUS - 2*tHuH) + mZS*(14*pow(mUS,2) |
---|
2038 | - 15*tHS - 44*tH*uH - 15*uHS + 2*mUS*tHuH) ); |
---|
2039 | double F2 = 2*tHS*uHS*tHuH*( -8*pow(mZS,2)*tHuH |
---|
2040 | + 4*mZS*(tHS + 3*tH*uH + uHS) |
---|
2041 | + 3*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) ); |
---|
2042 | double F4 = -2*tHS*uHS*pow(tHuH,3)*(tHS + uHS - mZS*tHuH); |
---|
2043 | |
---|
2044 | double G0 = 4*tH*uH*( 6*pow(mZS,3)*(mUS - tH - uH)*tHuH |
---|
2045 | + pow(mZS,2)*( 9*tHC + 7*tHS*uH + 7*tH*uHS + 9*uHC |
---|
2046 | + 15*pow2(mUS)*tHuH - 2*mUS*(12*tHS + 19*tH*uH + 12*uHS) ) |
---|
2047 | + tH*uH*( 6*pow(mUS,3) - 9*pow(mUS,2)*tHuH |
---|
2048 | - mUS*(tHS + 12*tH*uH + uHS) |
---|
2049 | + 6*(tHC + 6*tHS*uH + 6*tH*uHS + uHC) ) |
---|
2050 | + mZS*(-3*tHQ + 25*tHC*uH + 58*tHS*uHS + 25*tH*uHC |
---|
2051 | - 3*uHQ + 6*pow(mUS,3)*tHuH |
---|
2052 | - pow(mUS,2)*(15*tHS + 2*tH*uH + 15*uHS) |
---|
2053 | + 2*mUS*(6*tHC - 11*tHS*uH - 11*tH*uHS + 6*uHC)) ); |
---|
2054 | double G2 = -4*tHS*uHS*tHuH*( -10*pow2(mZS)*tHuH |
---|
2055 | + 2*mZS*(3*tHS + 7*tH*uH + 3*uHS) |
---|
2056 | + 3*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) ); |
---|
2057 | double G4 = -2*F4; |
---|
2058 | |
---|
2059 | double H0 = 24*pow(mZS,3)*tH*uH*pow2(-mUS + tHuH) |
---|
2060 | - 6*pow(mZS,2)*tH*uH*( -9*pow(mUS,3) + 24*pow(mUS,2)*tHuH |
---|
2061 | - mUS*(21*tHS + 38*tH*uH + 21*uHS) |
---|
2062 | + 2*(3*tHC + 5*tHS*uH + 5*tH*uHS + 3*uHC) ) |
---|
2063 | - mZS*( 3*pow(mUS,4)*(tHS - 12*tH*uH + uHS) |
---|
2064 | - 2*tH*uH*pow2(tHuH)*(6*tHS - 29*tH*uH + 6*uHS) |
---|
2065 | - 6*pow(mUS,3)*(tHC - 16*tHS*uH - 16*tH*uHS + uHC) |
---|
2066 | + 54*mUS*tH*uH*(tHC + tHS*uH + tH*uHS + uHC) |
---|
2067 | + pow2(mUS)*(3*tHQ - 102*tHC*uH - 166*tHS*uHS |
---|
2068 | - 102*tH*uHC + 3*uHQ) ) |
---|
2069 | + tH*uH*( 6*pow(mUS,5) - 18*pow(mUS,4)*tHuH |
---|
2070 | - 12*pow(mUS,2)*pow(tHuH,3) |
---|
2071 | + 3*pow(mUS,3)*(7*tHS + 12*tH*uH + 7*uHS) |
---|
2072 | - 18*tH*uH*(tHC + 5*tHS*uH + 5*tH*uHS + uHC) |
---|
2073 | + mUS*(3*tHQ + 32*tHC*uH + 78*tHS*uHS + 32*tH*uHC + 3*uHQ) ); |
---|
2074 | double H2 = 2*tHS*uHS*pow2(tHuH)*( -12*pow2(mZS) + 8*mZS*tHuH |
---|
2075 | + 3*(tHS + 4*tH*uH + uHS) ); |
---|
2076 | double H4 = F4; |
---|
2077 | |
---|
2078 | eDsigma0 = A0*( F0 + 1/mUS*F2 + 1/pow2(mUS)*F4 |
---|
2079 | + eDratio*(G0 + 1/mUS*G2 + 1/pow2(mUS)*G4) |
---|
2080 | + pow2(eDratio)*(H0 + 1/mUS*H2 + 1/pow2(mUS)*H4) ); |
---|
2081 | |
---|
2082 | } else { |
---|
2083 | |
---|
2084 | eDsigma0 = 0; |
---|
2085 | |
---|
2086 | } |
---|
2087 | |
---|
2088 | } |
---|
2089 | |
---|
2090 | //-------------------------------------------------------------------------- |
---|
2091 | |
---|
2092 | double Sigma2ffbar2LEDUnparticlegamma::sigmaHat() { |
---|
2093 | |
---|
2094 | // Electroweak couplings.. |
---|
2095 | int idAbs = abs(id1); |
---|
2096 | double facEWS = 4 * M_PI * alpEM * couplingsPtr->ef2(idAbs); |
---|
2097 | |
---|
2098 | // Mass Spectrum, (m^2)^(d-2) |
---|
2099 | double tmpExp = eDdU - 2; |
---|
2100 | double facSpect = pow(mUS, tmpExp); |
---|
2101 | |
---|
2102 | // Total cross section |
---|
2103 | double sigma = eDconstantTerm * facEWS * facSpect * eDsigma0; |
---|
2104 | |
---|
2105 | // If f fbar are quarks |
---|
2106 | if (idAbs < 9) sigma /= 3.; |
---|
2107 | |
---|
2108 | // Related to mass spactrum weighting. |
---|
2109 | sigma /= runBW3; |
---|
2110 | |
---|
2111 | // Truncate sH region or use form factor. |
---|
2112 | // Form factor uses either pythia8 renormScale2 |
---|
2113 | // or E_jet in cms. |
---|
2114 | if (eDcutoff == 1) { |
---|
2115 | if (sH > pow2(eDLambdaU) ) { sigma *= pow(eDLambdaU,4)/pow2(sH); } |
---|
2116 | } else if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
2117 | double tmPmu = sqrt(Q2RenSave); |
---|
2118 | if (eDcutoff == 3) tmPmu = (sH + s4 - s3) / (2 * mH); |
---|
2119 | double tmPformfact = tmPmu / (eDtff * eDLambdaU); |
---|
2120 | double tmPexp = double(eDnGrav) + 2; |
---|
2121 | sigma *= 1 / (1 + pow(tmPformfact, tmPexp)); |
---|
2122 | } |
---|
2123 | |
---|
2124 | return sigma; |
---|
2125 | |
---|
2126 | } |
---|
2127 | |
---|
2128 | //-------------------------------------------------------------------------- |
---|
2129 | |
---|
2130 | void Sigma2ffbar2LEDUnparticlegamma::setIdColAcol() { |
---|
2131 | |
---|
2132 | // Flavours trivial. |
---|
2133 | setId( id1, id2, eDidG, 22); |
---|
2134 | |
---|
2135 | // Colour flow topologies. Swap when antiquarks. |
---|
2136 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0); |
---|
2137 | else setColAcol( 0, 0, 0, 0, 0, 0); |
---|
2138 | if (id1 < 0) swapColAcol(); |
---|
2139 | |
---|
2140 | } |
---|
2141 | |
---|
2142 | //========================================================================== |
---|
2143 | |
---|
2144 | // Sigma2ffbar2LEDgammagamma class. |
---|
2145 | // Cross section for f fbar -> (LED G*/U*) -> gamma gamma |
---|
2146 | // (virtual graviton/unparticle exchange). |
---|
2147 | |
---|
2148 | //-------------------------------------------------------------------------- |
---|
2149 | |
---|
2150 | void Sigma2ffbar2LEDgammagamma::initProc() { |
---|
2151 | |
---|
2152 | // Init model parameters. |
---|
2153 | if (eDgraviton) { |
---|
2154 | eDspin = 2; |
---|
2155 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2156 | eDdU = 2; |
---|
2157 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2158 | eDlambda = 1; |
---|
2159 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
2160 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2161 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2162 | } else { |
---|
2163 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
2164 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
2165 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
2166 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
2167 | eDnegInt = 0; |
---|
2168 | } |
---|
2169 | |
---|
2170 | // Model dependent constants. |
---|
2171 | if (eDgraviton) { |
---|
2172 | eDlambda2chi = 4*M_PI; |
---|
2173 | if (eDnegInt == 1) eDlambda2chi *= -1.; |
---|
2174 | } else { |
---|
2175 | double tmPAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
2176 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
2177 | double tmPdUpi = eDdU * M_PI; |
---|
2178 | eDlambda2chi = pow2(eDlambda) * tmPAdU / (2 * sin(tmPdUpi)); |
---|
2179 | } |
---|
2180 | |
---|
2181 | // Model parameter check (if not applicable, sigma = 0). |
---|
2182 | // Note: SM contribution still generated. |
---|
2183 | if ( !(eDspin==0 || eDspin==2) ) { |
---|
2184 | eDlambda2chi = 0; |
---|
2185 | infoPtr->errorMsg("Error in Sigma2ffbar2LEDgammagamma::initProc: " |
---|
2186 | "Incorrect spin value (turn process off)!"); |
---|
2187 | } else if ( !eDgraviton && (eDdU >= 2)) { |
---|
2188 | eDlambda2chi = 0; |
---|
2189 | infoPtr->errorMsg("Error in Sigma2ffbar2LEDgammagamma::initProc: " |
---|
2190 | "This process requires dU < 2 (turn process off)!"); |
---|
2191 | } |
---|
2192 | |
---|
2193 | } |
---|
2194 | |
---|
2195 | //-------------------------------------------------------------------------- |
---|
2196 | |
---|
2197 | void Sigma2ffbar2LEDgammagamma::sigmaKin() { |
---|
2198 | |
---|
2199 | // Mandelstam variables. |
---|
2200 | double sHS = pow2(sH); |
---|
2201 | double sHQ = pow(sH, 4); |
---|
2202 | double tHS = pow2(tH); |
---|
2203 | double uHS = pow2(uH); |
---|
2204 | |
---|
2205 | // Form factor. |
---|
2206 | double tmPeffLambdaU = eDLambdaU; |
---|
2207 | if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
2208 | double tmPffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaU); |
---|
2209 | double tmPexp = double(eDnGrav) + 2; |
---|
2210 | double tmPformfact = 1 + pow(tmPffterm, tmPexp); |
---|
2211 | tmPeffLambdaU *= pow(tmPformfact,0.25); |
---|
2212 | } |
---|
2213 | |
---|
2214 | // ME from spin-0 and spin-2 unparticles |
---|
2215 | // including extra 1/sHS from 2-to-2 phase space. |
---|
2216 | if (eDspin == 0) { |
---|
2217 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2218 | double tmPexp = 2 * eDdU - 1; |
---|
2219 | eDterm1 = pow(tmPsLambda2,tmPexp); |
---|
2220 | eDterm1 /= sHS; |
---|
2221 | } else { |
---|
2222 | eDterm1 = (uH / tH + tH / uH); |
---|
2223 | eDterm1 /= sHS; |
---|
2224 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2225 | double tmPexp = eDdU; |
---|
2226 | eDterm2 = pow(tmPsLambda2,tmPexp) * (uHS + tHS) / sHS; |
---|
2227 | eDterm2 /= sHS; |
---|
2228 | tmPexp = 2 * eDdU; |
---|
2229 | eDterm3 = pow(tmPsLambda2,tmPexp) * tH * uH * (uHS + tHS) / sHQ; |
---|
2230 | eDterm3 /= sHS; |
---|
2231 | } |
---|
2232 | |
---|
2233 | } |
---|
2234 | |
---|
2235 | //-------------------------------------------------------------------------- |
---|
2236 | |
---|
2237 | double Sigma2ffbar2LEDgammagamma::sigmaHat() { |
---|
2238 | |
---|
2239 | // Incoming fermion flavor. |
---|
2240 | int idAbs = abs(id1); |
---|
2241 | |
---|
2242 | // Couplings and constants. |
---|
2243 | // Note: ME already contain 1/2 for identical |
---|
2244 | // particles in the final state. |
---|
2245 | double sigma = 0; |
---|
2246 | if (eDspin == 0) { |
---|
2247 | sigma = pow2(eDlambda2chi) * eDterm1 / 8; |
---|
2248 | } else { |
---|
2249 | double tmPe2Q2 = 4 * M_PI * alpEM * couplingsPtr->ef2(idAbs); |
---|
2250 | double tmPdUpi = eDdU * M_PI; |
---|
2251 | sigma = pow2(tmPe2Q2) * eDterm1 |
---|
2252 | - tmPe2Q2 * eDlambda2chi * cos(tmPdUpi) * eDterm2 |
---|
2253 | + pow2(eDlambda2chi) * eDterm3 / 4; |
---|
2254 | } |
---|
2255 | |
---|
2256 | // dsigma/dt, 2-to-2 phase space factors. |
---|
2257 | sigma /= 16 * M_PI; |
---|
2258 | |
---|
2259 | // If f fbar are quarks. |
---|
2260 | if (idAbs < 9) sigma /= 3.; |
---|
2261 | |
---|
2262 | return sigma; |
---|
2263 | } |
---|
2264 | |
---|
2265 | //-------------------------------------------------------------------------- |
---|
2266 | |
---|
2267 | void Sigma2ffbar2LEDgammagamma::setIdColAcol() { |
---|
2268 | |
---|
2269 | // Flavours trivial. |
---|
2270 | setId( id1, id2, 22, 22); |
---|
2271 | |
---|
2272 | // Colour flow topologies. Swap when antiquarks. |
---|
2273 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0, 0, 0); |
---|
2274 | else setColAcol( 0, 0, 0, 0, 0, 0, 0, 0); |
---|
2275 | if (id1 < 0) swapColAcol(); |
---|
2276 | |
---|
2277 | } |
---|
2278 | |
---|
2279 | //========================================================================== |
---|
2280 | |
---|
2281 | // Sigma2gg2LEDgammagamma class. |
---|
2282 | // Cross section for g g -> (LED G*/U*) -> gamma gamma |
---|
2283 | // (virtual graviton/unparticle exchange). |
---|
2284 | |
---|
2285 | //-------------------------------------------------------------------------- |
---|
2286 | |
---|
2287 | void Sigma2gg2LEDgammagamma::initProc() { |
---|
2288 | |
---|
2289 | // Init model parameters. |
---|
2290 | if (eDgraviton) { |
---|
2291 | eDspin = 2; |
---|
2292 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2293 | eDdU = 2; |
---|
2294 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2295 | eDlambda = 1; |
---|
2296 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2297 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2298 | } else { |
---|
2299 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
2300 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
2301 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
2302 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
2303 | } |
---|
2304 | |
---|
2305 | // Model dependent constants. |
---|
2306 | if (eDgraviton) { |
---|
2307 | eDlambda2chi = 4 * M_PI; |
---|
2308 | |
---|
2309 | } else { |
---|
2310 | double tmPAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
2311 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
2312 | double tmPdUpi = eDdU * M_PI; |
---|
2313 | eDlambda2chi = pow2(eDlambda) * tmPAdU / (2 * sin(tmPdUpi)); |
---|
2314 | } |
---|
2315 | |
---|
2316 | // Model parameter check (if not applicable, sigma = 0). |
---|
2317 | if ( !(eDspin==0 || eDspin==2) ) { |
---|
2318 | eDlambda2chi = 0; |
---|
2319 | infoPtr->errorMsg("Error in Sigma2gg2LEDgammagamma::initProc: " |
---|
2320 | "Incorrect spin value (turn process off)!"); |
---|
2321 | } else if ( !eDgraviton && (eDdU >= 2)) { |
---|
2322 | eDlambda2chi = 0; |
---|
2323 | infoPtr->errorMsg("Error in Sigma2gg2LEDgammagamma::initProc: " |
---|
2324 | "This process requires dU < 2 (turn process off)!"); |
---|
2325 | } |
---|
2326 | |
---|
2327 | } |
---|
2328 | |
---|
2329 | //-------------------------------------------------------------------------- |
---|
2330 | |
---|
2331 | void Sigma2gg2LEDgammagamma::sigmaKin() { |
---|
2332 | |
---|
2333 | // Mandelstam variables. |
---|
2334 | double sHS = pow2(sH); |
---|
2335 | double sHQ = pow(sH, 4); |
---|
2336 | double tHQ = pow(tH, 4); |
---|
2337 | double uHQ = pow(uH, 4); |
---|
2338 | |
---|
2339 | // Form factor. |
---|
2340 | double tmPeffLambdaU = eDLambdaU; |
---|
2341 | if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
2342 | double tmPffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaU); |
---|
2343 | double tmPexp = double(eDnGrav) + 2; |
---|
2344 | double tmPformfact = 1 + pow(tmPffterm, tmPexp); |
---|
2345 | tmPeffLambdaU *= pow(tmPformfact,0.25); |
---|
2346 | } |
---|
2347 | |
---|
2348 | // ME from spin-0 and spin-2 unparticles. |
---|
2349 | if (eDspin == 0) { |
---|
2350 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2351 | double tmPexp = 2 * eDdU; |
---|
2352 | eDsigma0 = pow(tmPsLambda2,tmPexp); |
---|
2353 | } else { |
---|
2354 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2355 | double tmPexp = 2 * eDdU; |
---|
2356 | eDsigma0 = pow(tmPsLambda2,tmPexp) * (uHQ + tHQ) / sHQ; |
---|
2357 | } |
---|
2358 | |
---|
2359 | // extra 1/sHS from 2-to-2 phase space. |
---|
2360 | eDsigma0 /= sHS; |
---|
2361 | |
---|
2362 | } |
---|
2363 | |
---|
2364 | //-------------------------------------------------------------------------- |
---|
2365 | |
---|
2366 | double Sigma2gg2LEDgammagamma::sigmaHat() { |
---|
2367 | |
---|
2368 | // Couplings and constants. |
---|
2369 | // Note: ME already contain 1/2 for identical |
---|
2370 | // particles in the final state. |
---|
2371 | double sigma = eDsigma0; |
---|
2372 | if (eDspin == 0) { |
---|
2373 | sigma *= pow2(eDlambda2chi) / 256; |
---|
2374 | } else { |
---|
2375 | sigma *= pow2(eDlambda2chi) / 32; |
---|
2376 | } |
---|
2377 | |
---|
2378 | // dsigma/dt, 2-to-2 phase space factors. |
---|
2379 | sigma /= 16 * M_PI; |
---|
2380 | |
---|
2381 | return sigma; |
---|
2382 | } |
---|
2383 | |
---|
2384 | //-------------------------------------------------------------------------- |
---|
2385 | |
---|
2386 | void Sigma2gg2LEDgammagamma::setIdColAcol() { |
---|
2387 | |
---|
2388 | // Flavours trivial. |
---|
2389 | setId( 21, 21, 22, 22); |
---|
2390 | |
---|
2391 | // Colour flow topologies. |
---|
2392 | setColAcol( 1, 2, 2, 1, 0, 0, 0, 0); |
---|
2393 | |
---|
2394 | } |
---|
2395 | |
---|
2396 | //========================================================================== |
---|
2397 | |
---|
2398 | // Sigma2ffbar2LEDllbar class. |
---|
2399 | // Cross section for f fbar -> (LED G*/U*) -> l lbar |
---|
2400 | // (virtual graviton/unparticle exchange). |
---|
2401 | // Does not include t-channel contributions relevant for e^+e^- to e^+e^- |
---|
2402 | |
---|
2403 | //-------------------------------------------------------------------------- |
---|
2404 | |
---|
2405 | void Sigma2ffbar2LEDllbar::initProc() { |
---|
2406 | |
---|
2407 | // Init model parameters. |
---|
2408 | if (eDgraviton) { |
---|
2409 | eDspin = 2; |
---|
2410 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2411 | eDdU = 2; |
---|
2412 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2413 | eDlambda = 1; |
---|
2414 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
2415 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2416 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2417 | } else { |
---|
2418 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
2419 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
2420 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
2421 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
2422 | eDnxx = settingsPtr->mode("ExtraDimensionsUnpart:gXX"); |
---|
2423 | eDnxy = settingsPtr->mode("ExtraDimensionsUnpart:gXY"); |
---|
2424 | eDnegInt = 0; |
---|
2425 | } |
---|
2426 | |
---|
2427 | eDmZ = particleDataPtr->m0(23); |
---|
2428 | eDmZS = eDmZ * eDmZ; |
---|
2429 | eDGZ = particleDataPtr->mWidth(23); |
---|
2430 | eDGZS = eDGZ * eDGZ; |
---|
2431 | |
---|
2432 | // Model dependent constants. |
---|
2433 | if (eDgraviton) { |
---|
2434 | eDlambda2chi = 4*M_PI; |
---|
2435 | if (eDnegInt == 1) eDlambda2chi *= -1.; |
---|
2436 | } else { |
---|
2437 | double tmPAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
2438 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
2439 | double tmPdUpi = eDdU * M_PI; |
---|
2440 | eDlambda2chi = pow2(eDlambda) * tmPAdU / (2 * sin(tmPdUpi)); |
---|
2441 | } |
---|
2442 | |
---|
2443 | // Model parameter check (if not applicable, sigma = 0). |
---|
2444 | // Note: SM contribution still generated. |
---|
2445 | if ( !(eDspin==1 || eDspin==2) ) { |
---|
2446 | eDlambda2chi = 0; |
---|
2447 | infoPtr->errorMsg("Error in Sigma2ffbar2LEDllbar::initProc: " |
---|
2448 | "Incorrect spin value (turn process off)!"); |
---|
2449 | } else if ( !eDgraviton && (eDdU >= 2)) { |
---|
2450 | eDlambda2chi = 0; |
---|
2451 | infoPtr->errorMsg("Error in Sigma2ffbar2LEDllbar::initProc: " |
---|
2452 | "This process requires dU < 2 (turn process off)!"); |
---|
2453 | } |
---|
2454 | |
---|
2455 | } |
---|
2456 | |
---|
2457 | //-------------------------------------------------------------------------- |
---|
2458 | |
---|
2459 | void Sigma2ffbar2LEDllbar::sigmaKin() { |
---|
2460 | |
---|
2461 | // Mandelstam variables. |
---|
2462 | double tHS = pow2(tH); |
---|
2463 | double uHS = pow2(uH); |
---|
2464 | double tHC = pow(tH,3); |
---|
2465 | double uHC = pow(uH,3); |
---|
2466 | double tHQ = pow(tH,4); |
---|
2467 | double uHQ = pow(uH,4); |
---|
2468 | |
---|
2469 | // Form factor. |
---|
2470 | double tmPeffLambdaU = eDLambdaU; |
---|
2471 | if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
2472 | double tmPffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaU); |
---|
2473 | double tmPexp = double(eDnGrav) + 2; |
---|
2474 | double tmPformfact = 1 + pow(tmPffterm, tmPexp); |
---|
2475 | tmPeffLambdaU *= pow(tmPformfact,0.25); |
---|
2476 | } |
---|
2477 | |
---|
2478 | // ME from spin-1 and spin-2 unparticles |
---|
2479 | eDdenomPropZ = pow2(sH - eDmZS) + eDmZS * eDGZS; |
---|
2480 | eDrePropZ = (sH - eDmZS) / eDdenomPropZ; |
---|
2481 | eDimPropZ = -eDmZ * eDGZ / eDdenomPropZ; |
---|
2482 | eDrePropGamma = 1 / sH; |
---|
2483 | if (eDspin == 1) { |
---|
2484 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2485 | double tmPexp = eDdU - 2; |
---|
2486 | eDabsMeU = eDlambda2chi * pow(tmPsLambda2,tmPexp) |
---|
2487 | / pow2(tmPeffLambdaU); |
---|
2488 | } else { |
---|
2489 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2490 | double tmPexp = eDdU - 2; |
---|
2491 | double tmPA = -eDlambda2chi * pow(tmPsLambda2,tmPexp) |
---|
2492 | / (8 * pow(tmPeffLambdaU,4)); |
---|
2493 | eDabsAS = pow2(tmPA); |
---|
2494 | eDreA = tmPA * cos(M_PI * eDdU); |
---|
2495 | eDreABW = tmPA * ((sH - eDmZS) * cos(M_PI * eDdU) + eDmZ * eDGZ |
---|
2496 | * sin(M_PI * eDdU)) / eDdenomPropZ; |
---|
2497 | eDpoly1 = tHQ + uHQ - 6*tHC*uH - 6*tH*uHC + 18*tHS*uHS; |
---|
2498 | double tmPdiffUT = uH - tH; |
---|
2499 | eDpoly2 = pow(tmPdiffUT,3); |
---|
2500 | eDpoly3 = tHC - 3*tHS*uH - 3*tH*uHS + uHC; |
---|
2501 | } |
---|
2502 | |
---|
2503 | } |
---|
2504 | |
---|
2505 | //-------------------------------------------------------------------------- |
---|
2506 | |
---|
2507 | double Sigma2ffbar2LEDllbar::sigmaHat() { |
---|
2508 | |
---|
2509 | // Incoming fermion flavor. |
---|
2510 | int idAbs = abs(id1); |
---|
2511 | |
---|
2512 | // Couplings and constants. |
---|
2513 | // Qq = couplingsPtr->ef(idAbs), quark, i.e. id > 0. |
---|
2514 | // Ql = couplingsPtr->ef(11), electron. |
---|
2515 | double tmPe2QfQl = 4 * M_PI * alpEM * couplingsPtr->ef(idAbs) |
---|
2516 | * couplingsPtr->ef(11); |
---|
2517 | double tmPgvq = 0.25 * couplingsPtr->vf(idAbs); |
---|
2518 | double tmPgaq = 0.25 * couplingsPtr->af(idAbs); |
---|
2519 | double tmPgLq = tmPgvq + tmPgaq; |
---|
2520 | double tmPgRq = tmPgvq - tmPgaq; |
---|
2521 | double tmPgvl = 0.25 * couplingsPtr->vf(11); |
---|
2522 | double tmPgal = 0.25 * couplingsPtr->af(11); |
---|
2523 | double tmPgLl = tmPgvl + tmPgal; |
---|
2524 | double tmPgRl = tmPgvl - tmPgal; |
---|
2525 | double tmPe2s2c2 = 4 * M_PI * alpEM |
---|
2526 | / (couplingsPtr->sin2thetaW() * couplingsPtr->cos2thetaW()); |
---|
2527 | |
---|
2528 | // LL, RR, LR, RL couplings. |
---|
2529 | vector<double> tmPcoupZ; |
---|
2530 | tmPcoupZ.push_back(tmPe2s2c2 * tmPgLq * tmPgLl); |
---|
2531 | tmPcoupZ.push_back(tmPe2s2c2 * tmPgRq * tmPgRl); |
---|
2532 | tmPcoupZ.push_back(tmPe2s2c2 * tmPgRq * tmPgLl); |
---|
2533 | tmPcoupZ.push_back(tmPe2s2c2 * tmPgLq * tmPgRl); |
---|
2534 | vector<double> tmPcoupU; |
---|
2535 | if (eDnxx == 1) { |
---|
2536 | // LL |
---|
2537 | tmPcoupU.push_back(-1); |
---|
2538 | // RR |
---|
2539 | tmPcoupU.push_back(-1); |
---|
2540 | } else if (eDnxx == 2) { |
---|
2541 | // LL |
---|
2542 | tmPcoupU.push_back(0); |
---|
2543 | // RR |
---|
2544 | tmPcoupU.push_back(0); |
---|
2545 | } else { |
---|
2546 | // LL |
---|
2547 | tmPcoupU.push_back(1); |
---|
2548 | // RR |
---|
2549 | tmPcoupU.push_back(1); |
---|
2550 | } |
---|
2551 | if (eDnxy == 1) { |
---|
2552 | // RL |
---|
2553 | tmPcoupU.push_back(-1); |
---|
2554 | // LR |
---|
2555 | tmPcoupU.push_back(-1); |
---|
2556 | } else if (eDnxy == 2) { |
---|
2557 | // RL |
---|
2558 | tmPcoupU.push_back(0); |
---|
2559 | // LR |
---|
2560 | tmPcoupU.push_back(0); |
---|
2561 | } else { |
---|
2562 | // RL |
---|
2563 | tmPcoupU.push_back(1); |
---|
2564 | // LR |
---|
2565 | tmPcoupU.push_back(1); |
---|
2566 | } |
---|
2567 | |
---|
2568 | // Matrix elements |
---|
2569 | double tmPMES = 0; |
---|
2570 | if (eDspin == 1) { |
---|
2571 | |
---|
2572 | for (unsigned int i = 0; i<tmPcoupZ.size(); ++i) { |
---|
2573 | double tmPMS = pow2(tmPcoupU[i] * eDabsMeU) |
---|
2574 | + pow2(tmPe2QfQl * eDrePropGamma) |
---|
2575 | + pow2(tmPcoupZ[i]) / eDdenomPropZ |
---|
2576 | + 2 * cos(M_PI * eDdU) * tmPcoupU[i] * eDabsMeU |
---|
2577 | * tmPe2QfQl * eDrePropGamma |
---|
2578 | + 2 * cos(M_PI * eDdU) * tmPcoupU[i] * eDabsMeU |
---|
2579 | * tmPcoupZ[i] * eDrePropZ |
---|
2580 | + 2 * tmPe2QfQl * eDrePropGamma |
---|
2581 | * tmPcoupZ[i] * eDrePropZ |
---|
2582 | - 2 * sin(M_PI * eDdU) * tmPcoupU[i] * eDabsMeU |
---|
2583 | * tmPcoupZ[i] * eDimPropZ; |
---|
2584 | |
---|
2585 | if (i<2) { tmPMES += 4 * pow2(uH) * tmPMS; } |
---|
2586 | else if (i<4) { tmPMES += 4 * pow2(tH) * tmPMS; } |
---|
2587 | } |
---|
2588 | |
---|
2589 | } else { |
---|
2590 | |
---|
2591 | for (unsigned int i = 0; i<tmPcoupZ.size(); ++i) { |
---|
2592 | double tmPMS = pow2(tmPe2QfQl * eDrePropGamma) |
---|
2593 | + pow2(tmPcoupZ[i]) / eDdenomPropZ |
---|
2594 | + 2 * tmPe2QfQl * eDrePropGamma * tmPcoupZ[i] * eDrePropZ; |
---|
2595 | |
---|
2596 | if (i<2) { tmPMES += 4 * pow2(uH) * tmPMS; } |
---|
2597 | else if (i<4) { tmPMES += 4 * pow2(tH) * tmPMS; } |
---|
2598 | } |
---|
2599 | tmPMES += 8 * eDabsAS * eDpoly1; |
---|
2600 | tmPMES += 16 * tmPe2QfQl * eDrePropGamma * eDreA * eDpoly2; |
---|
2601 | tmPMES += 16 * tmPe2s2c2 * eDreABW * (tmPgaq * tmPgal * eDpoly3 |
---|
2602 | + tmPgvq * tmPgvl * eDpoly2); |
---|
2603 | |
---|
2604 | } |
---|
2605 | |
---|
2606 | // dsigma/dt, 2-to-2 phase space factors. |
---|
2607 | double sigma = 0.25 * tmPMES; // 0.25, is the spin average |
---|
2608 | sigma /= 16 * M_PI * pow2(sH); |
---|
2609 | |
---|
2610 | // If f fbar are quarks. |
---|
2611 | if (idAbs < 9) sigma /= 3.; |
---|
2612 | |
---|
2613 | // sigma(ffbar->llbar) = 3 * sigma(ffbar->eebar) |
---|
2614 | sigma *= 3.; |
---|
2615 | |
---|
2616 | return sigma; |
---|
2617 | } |
---|
2618 | |
---|
2619 | //-------------------------------------------------------------------------- |
---|
2620 | |
---|
2621 | void Sigma2ffbar2LEDllbar::setIdColAcol() { |
---|
2622 | |
---|
2623 | double tmPrand = rndmPtr->flat(); |
---|
2624 | // Flavours trivial. |
---|
2625 | if (tmPrand < 0.33333333) { setId( id1, id2, 11, -11); } |
---|
2626 | else if (tmPrand < 0.66666667) { setId( id1, id2, 13, -13); } |
---|
2627 | else { setId( id1, id2, 15, -15); } |
---|
2628 | |
---|
2629 | // tH defined between f and f': must swap tHat <-> uHat if id1 is fbar. |
---|
2630 | swapTU = (id2 > 0); |
---|
2631 | |
---|
2632 | // Colour flow topologies. Swap when antiquarks. |
---|
2633 | if (abs(id1) < 9) setColAcol( 1, 0, 0, 1, 0, 0, 0, 0); |
---|
2634 | else setColAcol( 0, 0, 0, 0, 0, 0, 0, 0); |
---|
2635 | if (id1 < 0) swapColAcol(); |
---|
2636 | |
---|
2637 | } |
---|
2638 | |
---|
2639 | //========================================================================== |
---|
2640 | |
---|
2641 | // Sigma2gg2LEDllbar class. |
---|
2642 | // Cross section for g g -> (LED G*/U*) -> l lbar |
---|
2643 | // (virtual graviton/unparticle exchange). |
---|
2644 | |
---|
2645 | //-------------------------------------------------------------------------- |
---|
2646 | |
---|
2647 | void Sigma2gg2LEDllbar::initProc() { |
---|
2648 | |
---|
2649 | // Init model parameters. |
---|
2650 | if (eDgraviton) { |
---|
2651 | eDspin = 2; |
---|
2652 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2653 | eDdU = 2; |
---|
2654 | eDLambdaU = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2655 | eDlambda = 1; |
---|
2656 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2657 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2658 | } else { |
---|
2659 | eDspin = settingsPtr->mode("ExtraDimensionsUnpart:spinU"); |
---|
2660 | eDdU = settingsPtr->parm("ExtraDimensionsUnpart:dU"); |
---|
2661 | eDLambdaU = settingsPtr->parm("ExtraDimensionsUnpart:LambdaU"); |
---|
2662 | eDlambda = settingsPtr->parm("ExtraDimensionsUnpart:lambda"); |
---|
2663 | } |
---|
2664 | |
---|
2665 | // Model dependent constants. |
---|
2666 | if (eDgraviton) { |
---|
2667 | eDlambda2chi = 4 * M_PI; |
---|
2668 | |
---|
2669 | } else { |
---|
2670 | double tmPAdU = 16 * pow2(M_PI) * sqrt(M_PI) / pow(2. * M_PI, 2. * eDdU) |
---|
2671 | * GammaReal(eDdU + 0.5) / (GammaReal(eDdU - 1.) * GammaReal(2. * eDdU)); |
---|
2672 | double tmPdUpi = eDdU * M_PI; |
---|
2673 | eDlambda2chi = pow2(eDlambda) * tmPAdU / (2 * sin(tmPdUpi)); |
---|
2674 | } |
---|
2675 | |
---|
2676 | // Model parameter check (if not applicable, sigma = 0). |
---|
2677 | if ( !(eDspin==2) ) { |
---|
2678 | eDlambda2chi = 0; |
---|
2679 | infoPtr->errorMsg("Error in Sigma2gg2LEDllbar::initProc: " |
---|
2680 | "Incorrect spin value (turn process off)!"); |
---|
2681 | } else if ( !eDgraviton && (eDdU >= 2)) { |
---|
2682 | eDlambda2chi = 0; |
---|
2683 | infoPtr->errorMsg("Error in Sigma2gg2LEDllbar::initProc: " |
---|
2684 | "This process requires dU < 2 (turn process off)!"); |
---|
2685 | } |
---|
2686 | |
---|
2687 | } |
---|
2688 | |
---|
2689 | //-------------------------------------------------------------------------- |
---|
2690 | |
---|
2691 | void Sigma2gg2LEDllbar::sigmaKin() { |
---|
2692 | |
---|
2693 | // Form factor. |
---|
2694 | double tmPeffLambdaU = eDLambdaU; |
---|
2695 | if (eDgraviton && ((eDcutoff == 2) || (eDcutoff == 3))) { |
---|
2696 | double tmPffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaU); |
---|
2697 | double tmPexp = double(eDnGrav) + 2; |
---|
2698 | double tmPformfact = 1 + pow(tmPffterm, tmPexp); |
---|
2699 | tmPeffLambdaU *= pow(tmPformfact,0.25); |
---|
2700 | } |
---|
2701 | |
---|
2702 | // ME from spin-2 unparticle. |
---|
2703 | double tmPsLambda2 = sH / pow2(tmPeffLambdaU); |
---|
2704 | double tmPexp = eDdU - 2; |
---|
2705 | double tmPA = -eDlambda2chi * pow(tmPsLambda2,tmPexp) |
---|
2706 | / (8 * pow(tmPeffLambdaU,4)); |
---|
2707 | eDsigma0 = 4 * pow2(tmPA) * uH * tH * (pow2(uH) + pow2(tH)); |
---|
2708 | |
---|
2709 | // extra 1/sHS from 2-to-2 phase space. |
---|
2710 | eDsigma0 /= 16 * M_PI * pow2(sH); |
---|
2711 | |
---|
2712 | // sigma(ffbar->llbar) = 3 * sigma(ffbar->eebar) |
---|
2713 | eDsigma0 *= 3.; |
---|
2714 | |
---|
2715 | } |
---|
2716 | |
---|
2717 | //-------------------------------------------------------------------------- |
---|
2718 | |
---|
2719 | void Sigma2gg2LEDllbar::setIdColAcol() { |
---|
2720 | |
---|
2721 | double tmPrand = rndmPtr->flat(); |
---|
2722 | // Flavours trivial. |
---|
2723 | if (tmPrand < 0.33333333) { setId( 21, 21, 11, -11); } |
---|
2724 | else if (tmPrand < 0.66666667) { setId( 21, 21, 13, -13); } |
---|
2725 | else { setId( 21, 21, 15, -15); } |
---|
2726 | |
---|
2727 | // Colour flow topologies. |
---|
2728 | setColAcol( 1, 2, 2, 1, 0, 0, 0, 0); |
---|
2729 | |
---|
2730 | } |
---|
2731 | |
---|
2732 | //========================================================================== |
---|
2733 | |
---|
2734 | // Sigma2gg2LEDgg class. |
---|
2735 | // Cross section for g g -> (LED G*) -> g g. |
---|
2736 | |
---|
2737 | //-------------------------------------------------------------------------- |
---|
2738 | |
---|
2739 | // Initialize process. |
---|
2740 | |
---|
2741 | void Sigma2gg2LEDgg::initProc() { |
---|
2742 | |
---|
2743 | // Read model parameters. |
---|
2744 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
2745 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2746 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
2747 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2748 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
2749 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2750 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2751 | |
---|
2752 | } |
---|
2753 | |
---|
2754 | //-------------------------------------------------------------------------- |
---|
2755 | |
---|
2756 | // Evaluate d(sigmaHat)/d(tHat) - no incoming flavour dependence. |
---|
2757 | |
---|
2758 | void Sigma2gg2LEDgg::sigmaKin() { |
---|
2759 | |
---|
2760 | // Get S(x) values for G amplitude. |
---|
2761 | complex sS(0., 0.); |
---|
2762 | complex sT(0., 0.); |
---|
2763 | complex sU(0., 0.); |
---|
2764 | if (eDopMode == 0) { |
---|
2765 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2766 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2767 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2768 | } else { |
---|
2769 | // Form factor. |
---|
2770 | double effLambda = eDLambdaT; |
---|
2771 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
2772 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
2773 | double exp = double(eDnGrav) + 2.; |
---|
2774 | double formfa = 1. + pow(ffterm, exp); |
---|
2775 | effLambda *= pow(formfa,0.25); |
---|
2776 | } |
---|
2777 | sS = 4.*M_PI/pow(effLambda,4); |
---|
2778 | sT = 4.*M_PI/pow(effLambda,4); |
---|
2779 | sU = 4.*M_PI/pow(effLambda,4); |
---|
2780 | if (eDnegInt == 1) { |
---|
2781 | sS *= -1.; |
---|
2782 | sT *= -1.; |
---|
2783 | sU *= -1.; |
---|
2784 | } |
---|
2785 | } |
---|
2786 | |
---|
2787 | // Calculate kinematics dependence. |
---|
2788 | double sH3 = sH*sH2; |
---|
2789 | double tH3 = tH*tH2; |
---|
2790 | double uH3 = uH*uH2; |
---|
2791 | |
---|
2792 | sigTS = (128. * pow2(M_PI) * pow2(alpS)) * (9./4.) |
---|
2793 | * (tH2 / sH2 + 2. * tH / sH + 3. + 2. * sH / tH + sH2 / tH2) |
---|
2794 | + 24.*M_PI*alpS*( (sH3/tH + tH2 + 3.*(sH*tH + sH2))*sS.real() |
---|
2795 | + (tH3/sH + sH2 + 3.*(tH*sH + tH2))*sT.real()) |
---|
2796 | + pow2(uH2)*( 4.*real(sS*conj(sS)) + sS.real()*sT.real() |
---|
2797 | + sS.imag()*sT.imag() + 4.*real(sT*conj(sT))); |
---|
2798 | |
---|
2799 | |
---|
2800 | sigUS = (128. * pow2(M_PI) * pow2(alpS)) * (9./4.) |
---|
2801 | * (uH2 / sH2 + 2. * uH / sH + 3. + 2. * sH / uH + sH2 / uH2) |
---|
2802 | + 24.*M_PI*alpS*( (sH3/uH + uH2 + 3.*(sH*uH + sH2))*sS.real() |
---|
2803 | + (uH3/sH + sH2 + 3.*(uH*sH + uH2))*sU.real()) |
---|
2804 | + pow2(tH2)*( 4.*real(sS*conj(sS)) + sS.real()*sU.real() |
---|
2805 | + sS.imag()*sU.imag() + 4.*real(sU*conj(sU))); |
---|
2806 | |
---|
2807 | sigTU = (128. * pow2(M_PI) * pow2(alpS)) * (9./4.) |
---|
2808 | * (tH2 / uH2 + 2. * tH / uH + 3. + 2. * uH / tH + uH2 / tH2) |
---|
2809 | + 24.*M_PI*alpS*( (tH3/uH + uH2 + 3.*(tH*uH + tH2))*sT.real() |
---|
2810 | + (uH3/tH + tH2 + 3.*(uH*tH + uH2))*sU.real()) |
---|
2811 | + pow2(sH2)*( 4.*real(sT*conj(sT)) + sT.real()*sU.real() |
---|
2812 | + sT.imag()*sU.imag() + 4.*real(sU*conj(sU))); |
---|
2813 | |
---|
2814 | sigSum = sigTS + sigUS + sigTU; |
---|
2815 | |
---|
2816 | // Answer contains factor 1/2 from identical gluons. |
---|
2817 | sigma = 0.5 * sigSum / (128. * M_PI * sH2); |
---|
2818 | |
---|
2819 | } |
---|
2820 | |
---|
2821 | //-------------------------------------------------------------------------- |
---|
2822 | |
---|
2823 | // Select identity, colour and anticolour. |
---|
2824 | |
---|
2825 | void Sigma2gg2LEDgg::setIdColAcol() { |
---|
2826 | |
---|
2827 | // Flavours are trivial. |
---|
2828 | setId( id1, id2, 21, 21); |
---|
2829 | |
---|
2830 | // Three colour flow topologies, each with two orientations. |
---|
2831 | double sigRand = sigSum * rndmPtr->flat(); |
---|
2832 | if (sigRand < sigTS) setColAcol( 1, 2, 2, 3, 1, 4, 4, 3); |
---|
2833 | else if (sigRand < sigTS + sigUS) |
---|
2834 | setColAcol( 1, 2, 3, 1, 3, 4, 4, 2); |
---|
2835 | else setColAcol( 1, 2, 3, 4, 1, 4, 3, 2); |
---|
2836 | if (rndmPtr->flat() > 0.5) swapColAcol(); |
---|
2837 | |
---|
2838 | } |
---|
2839 | |
---|
2840 | //========================================================================== |
---|
2841 | |
---|
2842 | // Sigma2gg2LEDqqbar class. |
---|
2843 | // Cross section for g g -> (LED G*) -> q qbar. |
---|
2844 | |
---|
2845 | //-------------------------------------------------------------------------- |
---|
2846 | |
---|
2847 | // Initialize process. |
---|
2848 | |
---|
2849 | void Sigma2gg2LEDqqbar::initProc() { |
---|
2850 | |
---|
2851 | // Read number of quarks to be considered in massless approximation |
---|
2852 | // as well as model parameters. |
---|
2853 | nQuarkNew = settingsPtr->mode("ExtraDimensionsLED:nQuarkNew"); |
---|
2854 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
2855 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2856 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
2857 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2858 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
2859 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2860 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2861 | |
---|
2862 | } |
---|
2863 | |
---|
2864 | //-------------------------------------------------------------------------- |
---|
2865 | |
---|
2866 | // Evaluate d(sigmaHat)/d(tHat) - no incoming flavour dependence. |
---|
2867 | |
---|
2868 | void Sigma2gg2LEDqqbar::sigmaKin() { |
---|
2869 | |
---|
2870 | // Get S(x) values for G amplitude. |
---|
2871 | complex sS(0., 0.); |
---|
2872 | complex sT(0., 0.); |
---|
2873 | complex sU(0., 0.); |
---|
2874 | if (eDopMode == 0) { |
---|
2875 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2876 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2877 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2878 | } else { |
---|
2879 | // Form factor. |
---|
2880 | double effLambda = eDLambdaT; |
---|
2881 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
2882 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
2883 | double exp = double(eDnGrav) + 2.; |
---|
2884 | double formfa = 1. + pow(ffterm, exp); |
---|
2885 | effLambda *= pow(formfa,0.25); |
---|
2886 | } |
---|
2887 | sS = 4.*M_PI/pow(effLambda,4); |
---|
2888 | sT = 4.*M_PI/pow(effLambda,4); |
---|
2889 | sU = 4.*M_PI/pow(effLambda,4); |
---|
2890 | if (eDnegInt == 1) { |
---|
2891 | sS *= -1.; |
---|
2892 | sT *= -1.; |
---|
2893 | sU *= -1.; |
---|
2894 | } |
---|
2895 | } |
---|
2896 | |
---|
2897 | // Pick new flavour. |
---|
2898 | idNew = 1 + int( nQuarkNew * rndmPtr->flat() ); |
---|
2899 | mNew = particleDataPtr->m0(idNew); |
---|
2900 | m2New = mNew*mNew; |
---|
2901 | |
---|
2902 | // Calculate kinematics dependence. |
---|
2903 | sigTS = 0.; |
---|
2904 | sigUS = 0.; |
---|
2905 | if (sH > 4. * m2New) { |
---|
2906 | double tH3 = tH*tH2; |
---|
2907 | double uH3 = uH*uH2; |
---|
2908 | sigTS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
2909 | * ((1./6.) * uH / tH - (3./8.) * uH2 / sH2) |
---|
2910 | - 0.5 * M_PI * alpS * uH2 * sS.real() |
---|
2911 | + (3./16.) * uH3 * tH * real(sS*conj(sS)); |
---|
2912 | sigUS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
2913 | * ((1./6.) * tH / uH - (3./8.) * tH2 / sH2) |
---|
2914 | - 0.5 * M_PI * alpS * tH2 * sS.real() |
---|
2915 | + (3./16.) * tH3 * uH * real(sS*conj(sS)); |
---|
2916 | } |
---|
2917 | sigSum = sigTS + sigUS; |
---|
2918 | |
---|
2919 | // Answer is proportional to number of outgoing flavours. |
---|
2920 | sigma = nQuarkNew * sigSum / (16. * M_PI * sH2); |
---|
2921 | |
---|
2922 | } |
---|
2923 | |
---|
2924 | //-------------------------------------------------------------------------- |
---|
2925 | |
---|
2926 | // Select identity, colour and anticolour. |
---|
2927 | |
---|
2928 | void Sigma2gg2LEDqqbar::setIdColAcol() { |
---|
2929 | |
---|
2930 | // Flavours are trivial. |
---|
2931 | setId( id1, id2, idNew, -idNew); |
---|
2932 | |
---|
2933 | // Two colour flow topologies. |
---|
2934 | double sigRand = sigSum * rndmPtr->flat(); |
---|
2935 | if (sigRand < sigTS) setColAcol( 1, 2, 2, 3, 1, 0, 0, 3); |
---|
2936 | else setColAcol( 1, 2, 3, 1, 3, 0, 0, 2); |
---|
2937 | |
---|
2938 | } |
---|
2939 | |
---|
2940 | //========================================================================== |
---|
2941 | |
---|
2942 | // Sigma2qg2LEDqg class. |
---|
2943 | // Cross section for q g -> (LED G*) -> q g. |
---|
2944 | |
---|
2945 | //-------------------------------------------------------------------------- |
---|
2946 | |
---|
2947 | // Initialize process. |
---|
2948 | |
---|
2949 | void Sigma2qg2LEDqg::initProc() { |
---|
2950 | |
---|
2951 | // Read model parameters. |
---|
2952 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
2953 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
2954 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
2955 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
2956 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
2957 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
2958 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
2959 | |
---|
2960 | } |
---|
2961 | |
---|
2962 | //-------------------------------------------------------------------------- |
---|
2963 | |
---|
2964 | // Evaluate d(sigmaHat)/d(tHat) - no incoming flavour dependence. |
---|
2965 | |
---|
2966 | void Sigma2qg2LEDqg::sigmaKin() { |
---|
2967 | |
---|
2968 | // Get S(x) values for G amplitude. |
---|
2969 | complex sS(0., 0.); |
---|
2970 | complex sT(0., 0.); |
---|
2971 | complex sU(0., 0.); |
---|
2972 | if (eDopMode == 0) { |
---|
2973 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2974 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2975 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
2976 | } else { |
---|
2977 | // Form factor. |
---|
2978 | double effLambda = eDLambdaT; |
---|
2979 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
2980 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
2981 | double exp = double(eDnGrav) + 2.; |
---|
2982 | double formfa = 1. + pow(ffterm, exp); |
---|
2983 | effLambda *= pow(formfa,0.25); |
---|
2984 | } |
---|
2985 | sS = 4.*M_PI/pow(effLambda,4); |
---|
2986 | sT = 4.*M_PI/pow(effLambda,4); |
---|
2987 | sU = 4.*M_PI/pow(effLambda,4); |
---|
2988 | if (eDnegInt == 1) { |
---|
2989 | sS *= -1.; |
---|
2990 | sT *= -1.; |
---|
2991 | sU *= -1.; |
---|
2992 | } |
---|
2993 | } |
---|
2994 | |
---|
2995 | // Calculate kinematics dependence. |
---|
2996 | double sH3 = sH*sH2; |
---|
2997 | double uH3 = uH*uH2; |
---|
2998 | sigTS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
2999 | * (uH2 / tH2 - (4./9.) * uH / sH) |
---|
3000 | + (4./3.) * M_PI * alpS * uH2 * sT.real() |
---|
3001 | - 0.5 * uH3 * sH * real(sT*conj(sT)); |
---|
3002 | sigTU = (16. * pow2(M_PI) * pow2(alpS)) |
---|
3003 | * (sH2 / tH2 - (4./9.) * sH / uH) |
---|
3004 | + (4./3.) * M_PI * alpS * sH2 * sT.real() |
---|
3005 | - 0.5 * sH3 * uH * real(sT*conj(sT)); |
---|
3006 | sigSum = sigTS + sigTU; |
---|
3007 | |
---|
3008 | // Answer. |
---|
3009 | sigma = sigSum / (16. * M_PI * sH2); |
---|
3010 | |
---|
3011 | } |
---|
3012 | |
---|
3013 | //-------------------------------------------------------------------------- |
---|
3014 | |
---|
3015 | // Select identity, colour and anticolour. |
---|
3016 | |
---|
3017 | void Sigma2qg2LEDqg::setIdColAcol() { |
---|
3018 | |
---|
3019 | // Outgoing = incoming flavours. |
---|
3020 | setId( id1, id2, id1, id2); |
---|
3021 | |
---|
3022 | // Two colour flow topologies. Swap if first is gluon, or when antiquark. |
---|
3023 | double sigRand = sigSum * rndmPtr->flat(); |
---|
3024 | if (sigRand < sigTS) setColAcol( 1, 0, 2, 1, 3, 0, 2, 3); |
---|
3025 | else setColAcol( 1, 0, 2, 3, 2, 0, 1, 3); |
---|
3026 | if (id1 == 21) swapCol1234(); |
---|
3027 | if (id1 < 0 || id2 < 0) swapColAcol(); |
---|
3028 | |
---|
3029 | } |
---|
3030 | |
---|
3031 | //========================================================================== |
---|
3032 | |
---|
3033 | // Sigma2qq2LEDqq class. |
---|
3034 | // Cross section for q q(bar)' -> (LED G*) -> q q(bar)' |
---|
3035 | |
---|
3036 | //-------------------------------------------------------------------------- |
---|
3037 | |
---|
3038 | // Initialize process. |
---|
3039 | |
---|
3040 | void Sigma2qq2LEDqq::initProc() { |
---|
3041 | |
---|
3042 | // Read model parameters. |
---|
3043 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
3044 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
3045 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
3046 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
3047 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
3048 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
3049 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
3050 | |
---|
3051 | } |
---|
3052 | |
---|
3053 | //-------------------------------------------------------------------------- |
---|
3054 | |
---|
3055 | // Evaluate d(sigmaHat)/d(tHat), part independent of incoming flavour. |
---|
3056 | |
---|
3057 | void Sigma2qq2LEDqq::sigmaKin() { |
---|
3058 | |
---|
3059 | // Get S(x) values for G amplitude. |
---|
3060 | complex sS(0., 0.); |
---|
3061 | complex sT(0., 0.); |
---|
3062 | complex sU(0., 0.); |
---|
3063 | if (eDopMode == 0) { |
---|
3064 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3065 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3066 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3067 | } else { |
---|
3068 | // Form factor. |
---|
3069 | double effLambda = eDLambdaT; |
---|
3070 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
3071 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
3072 | double exp = double(eDnGrav) + 2.; |
---|
3073 | double formfa = 1. + pow(ffterm, exp); |
---|
3074 | effLambda *= pow(formfa,0.25); |
---|
3075 | } |
---|
3076 | sS = 4.*M_PI/pow(effLambda,4); |
---|
3077 | sT = 4.*M_PI/pow(effLambda,4); |
---|
3078 | sU = 4.*M_PI/pow(effLambda,4); |
---|
3079 | if (eDnegInt == 1) { |
---|
3080 | sS *= -1.; |
---|
3081 | sT *= -1.; |
---|
3082 | sU *= -1.; |
---|
3083 | } |
---|
3084 | } |
---|
3085 | |
---|
3086 | // Calculate kinematics dependence for different terms. |
---|
3087 | sigT = (4./9.) * (sH2 + uH2) / tH2; |
---|
3088 | sigU = (4./9.) * (sH2 + tH2) / uH2; |
---|
3089 | sigTU = - (8./27.) * sH2 / (tH * uH); |
---|
3090 | sigST = - (8./27.) * uH2 / (sH * tH); |
---|
3091 | // Graviton terms. |
---|
3092 | sigGrT1 = funLedG(tH, uH) * real(sT*conj(sT)) / 8.; |
---|
3093 | sigGrT2 = funLedG(tH, sH) * real(sT*conj(sT)) / 8.; |
---|
3094 | sigGrU = funLedG(uH, tH) * real(sU*conj(sU)) / 8.; |
---|
3095 | sigGrTU = (8./9.) * M_PI * alpS * sH2 |
---|
3096 | * ((4.*uH + tH)*sT.real()/uH + (4.*tH + uH)*sU.real()/tH) |
---|
3097 | + (sT.real()*sU.real() + sT.imag()*sU.imag()) |
---|
3098 | * (4.*tH + uH)*(4.*uH + tH) * sH2 / 48.; |
---|
3099 | sigGrST = (8./9.) * M_PI * alpS * uH2 |
---|
3100 | * ((4.*tH + sH)*sS.real()/tH + (4.*sH + tH)*sT.real()/sH) |
---|
3101 | + (sS.real()*sT.real() + sS.imag()*sT.imag()) |
---|
3102 | * (4.*sH + tH)*(4.*tH + sH) * uH2 / 48.; |
---|
3103 | |
---|
3104 | } |
---|
3105 | |
---|
3106 | //-------------------------------------------------------------------------- |
---|
3107 | |
---|
3108 | // Evaluate d(sigmaHat)/d(tHat), including incoming flavour dependence. |
---|
3109 | |
---|
3110 | double Sigma2qq2LEDqq::sigmaHat() { |
---|
3111 | |
---|
3112 | // Combine cross section terms; factor 1/2 when identical quarks. |
---|
3113 | if (id2 == id1) { |
---|
3114 | sigSum = (16. * pow2(M_PI) * pow2(alpS)) * (sigT + sigU + sigTU) |
---|
3115 | + sigGrT1 + sigGrU + sigGrTU; |
---|
3116 | sigSum *= 0.5; |
---|
3117 | } else if (id2 == -id1) { |
---|
3118 | sigSum = (16. * pow2(M_PI) * pow2(alpS)) * (sigT + sigST) |
---|
3119 | + sigGrT2 + sigGrST; |
---|
3120 | } else { |
---|
3121 | sigSum = 16. * pow2(M_PI) * pow2(alpS) * sigT + sigGrT1; |
---|
3122 | } |
---|
3123 | |
---|
3124 | // Answer. |
---|
3125 | return sigSum / (16. * M_PI * sH2); |
---|
3126 | |
---|
3127 | } |
---|
3128 | |
---|
3129 | //-------------------------------------------------------------------------- |
---|
3130 | |
---|
3131 | // Select identity, colour and anticolour. |
---|
3132 | |
---|
3133 | void Sigma2qq2LEDqq::setIdColAcol() { |
---|
3134 | |
---|
3135 | // Outgoing = incoming flavours. |
---|
3136 | setId( id1, id2, id1, id2); |
---|
3137 | |
---|
3138 | // Colour flow topologies. Swap when antiquarks. |
---|
3139 | double sigTtot = sigT + sigGrT2; |
---|
3140 | double sigUtot = sigU + sigGrU; |
---|
3141 | if (id1 * id2 > 0) setColAcol( 1, 0, 2, 0, 2, 0, 1, 0); |
---|
3142 | else setColAcol( 1, 0, 0, 1, 2, 0, 0, 2); |
---|
3143 | if (id2 == id1 && (sigTtot + sigUtot) * rndmPtr->flat() > sigTtot) |
---|
3144 | setColAcol( 1, 0, 2, 0, 1, 0, 2, 0); |
---|
3145 | if (id1 < 0) swapColAcol(); |
---|
3146 | |
---|
3147 | } |
---|
3148 | |
---|
3149 | //========================================================================== |
---|
3150 | |
---|
3151 | // Sigma2qqbar2LEDgg class. |
---|
3152 | // Cross section for q qbar -> (LED G*) -> g g. |
---|
3153 | |
---|
3154 | //-------------------------------------------------------------------------- |
---|
3155 | |
---|
3156 | // Initialize process. |
---|
3157 | |
---|
3158 | void Sigma2qqbar2LEDgg::initProc() { |
---|
3159 | |
---|
3160 | // Read model parameters. |
---|
3161 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
3162 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
3163 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
3164 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
3165 | eDnegInt = settingsPtr->mode("ExtraDimensionsLED:NegInt"); |
---|
3166 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
3167 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
3168 | |
---|
3169 | } |
---|
3170 | |
---|
3171 | //-------------------------------------------------------------------------- |
---|
3172 | |
---|
3173 | // Evaluate d(sigmaHat)/d(tHat) - no incoming flavour dependence. |
---|
3174 | |
---|
3175 | void Sigma2qqbar2LEDgg::sigmaKin() { |
---|
3176 | |
---|
3177 | // Get S(x) values for G amplitude. |
---|
3178 | complex sS(0., 0.); |
---|
3179 | complex sT(0., 0.); |
---|
3180 | complex sU(0., 0.); |
---|
3181 | if (eDopMode == 0) { |
---|
3182 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3183 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3184 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3185 | } else { |
---|
3186 | // Form factor. |
---|
3187 | double effLambda = eDLambdaT; |
---|
3188 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
3189 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
3190 | double exp = double(eDnGrav) + 2.; |
---|
3191 | double formfa = 1. + pow(ffterm, exp); |
---|
3192 | effLambda *= pow(formfa,0.25); |
---|
3193 | } |
---|
3194 | sS = 4.*M_PI/pow(effLambda,4); |
---|
3195 | sT = 4.*M_PI/pow(effLambda,4); |
---|
3196 | sU = 4.*M_PI/pow(effLambda,4); |
---|
3197 | if (eDnegInt == 1) { |
---|
3198 | sS *= -1.; |
---|
3199 | sT *= -1.; |
---|
3200 | sU *= -1.; |
---|
3201 | } |
---|
3202 | } |
---|
3203 | |
---|
3204 | // Calculate kinematics dependence. |
---|
3205 | double tH3 = tH*tH2; |
---|
3206 | double uH3 = uH*uH2; |
---|
3207 | sigTS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
3208 | * ((1./6.) * uH / tH - (3./8.) * uH2 / sH2) |
---|
3209 | - 0.5 * M_PI * alpS * uH2 * sS.real() |
---|
3210 | + (3./16.) * uH3 * tH * real(sS*conj(sS)); |
---|
3211 | sigUS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
3212 | * ((1./6.) * tH / uH - (3./8.) * tH2 / sH2) |
---|
3213 | - 0.5 * M_PI * alpS * tH2 * sS.real() |
---|
3214 | + (3./16.) * tH3 * uH * real(sS*conj(sS)); |
---|
3215 | |
---|
3216 | sigSum = sigTS + sigUS; |
---|
3217 | |
---|
3218 | // Answer contains factor 1/2 from identical gluons. |
---|
3219 | sigma = (64./9.) * 0.5 * sigSum / (16. * M_PI * sH2); |
---|
3220 | |
---|
3221 | } |
---|
3222 | |
---|
3223 | //-------------------------------------------------------------------------- |
---|
3224 | |
---|
3225 | // Select identity, colour and anticolour. |
---|
3226 | |
---|
3227 | void Sigma2qqbar2LEDgg::setIdColAcol() { |
---|
3228 | |
---|
3229 | // Outgoing flavours trivial. |
---|
3230 | setId( id1, id2, 21, 21); |
---|
3231 | |
---|
3232 | // Two colour flow topologies. Swap if first is antiquark. |
---|
3233 | double sigRand = sigSum * rndmPtr->flat(); |
---|
3234 | if (sigRand < sigTS) setColAcol( 1, 0, 0, 2, 1, 3, 3, 2); |
---|
3235 | else setColAcol( 1, 0, 0, 2, 3, 2, 1, 3); |
---|
3236 | if (id1 < 0) swapColAcol(); |
---|
3237 | |
---|
3238 | } |
---|
3239 | |
---|
3240 | //========================================================================== |
---|
3241 | |
---|
3242 | // Sigma2qqbar2LEDqqbarNew class. |
---|
3243 | // Cross section q qbar -> (LED G*) -> q' qbar'. |
---|
3244 | |
---|
3245 | //-------------------------------------------------------------------------- |
---|
3246 | |
---|
3247 | // Initialize process. |
---|
3248 | |
---|
3249 | void Sigma2qqbar2LEDqqbarNew::initProc() { |
---|
3250 | |
---|
3251 | // Read number of quarks to be considered in massless approximation |
---|
3252 | // as well as model parameters. |
---|
3253 | nQuarkNew = settingsPtr->mode("ExtraDimensionsLED:nQuarkNew"); |
---|
3254 | eDopMode = settingsPtr->mode("ExtraDimensionsLED:opMode"); |
---|
3255 | eDnGrav = settingsPtr->mode("ExtraDimensionsLED:n"); |
---|
3256 | eDMD = settingsPtr->parm("ExtraDimensionsLED:MD"); |
---|
3257 | eDLambdaT = settingsPtr->parm("ExtraDimensionsLED:LambdaT"); |
---|
3258 | eDcutoff = settingsPtr->mode("ExtraDimensionsLED:CutOffMode"); |
---|
3259 | eDtff = settingsPtr->parm("ExtraDimensionsLED:t"); |
---|
3260 | |
---|
3261 | } |
---|
3262 | |
---|
3263 | //-------------------------------------------------------------------------- |
---|
3264 | |
---|
3265 | // Evaluate d(sigmaHat)/d(tHat) - no incoming flavour dependence. |
---|
3266 | |
---|
3267 | void Sigma2qqbar2LEDqqbarNew::sigmaKin() { |
---|
3268 | |
---|
3269 | // Get S(x) values for G amplitude. |
---|
3270 | complex sS(0., 0.); |
---|
3271 | complex sT(0., 0.); |
---|
3272 | complex sU(0., 0.); |
---|
3273 | if (eDopMode == 0) { |
---|
3274 | sS = ampLedS( sH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3275 | sT = ampLedS( tH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3276 | sU = ampLedS( uH/pow2(eDLambdaT), eDnGrav, eDLambdaT, eDMD); |
---|
3277 | } else { |
---|
3278 | // Form factor. |
---|
3279 | double effLambda = eDLambdaT; |
---|
3280 | if ((eDcutoff == 2) || (eDcutoff == 3)) { |
---|
3281 | double ffterm = sqrt(Q2RenSave) / (eDtff * eDLambdaT); |
---|
3282 | double exp = double(eDnGrav) + 2.; |
---|
3283 | double formfa = 1. + pow(ffterm, exp); |
---|
3284 | effLambda *= pow(formfa,0.25); |
---|
3285 | } |
---|
3286 | sS = 4.*M_PI/pow(effLambda,4); |
---|
3287 | sT = 4.*M_PI/pow(effLambda,4); |
---|
3288 | sU = 4.*M_PI/pow(effLambda,4); |
---|
3289 | } |
---|
3290 | |
---|
3291 | // Pick new flavour. |
---|
3292 | idNew = 1 + int( nQuarkNew * rndmPtr->flat() ); |
---|
3293 | mNew = particleDataPtr->m0(idNew); |
---|
3294 | m2New = mNew*mNew; |
---|
3295 | |
---|
3296 | // Calculate kinematics dependence. |
---|
3297 | sigS = 0.; |
---|
3298 | if (sH > 4. * m2New) { |
---|
3299 | sigS = (16. * pow2(M_PI) * pow2(alpS)) |
---|
3300 | * (4./9.) * (tH2 + uH2) / sH2 |
---|
3301 | + funLedG(sH, tH) * real(sS*conj(sS)) / 8.; |
---|
3302 | } |
---|
3303 | // Answer is proportional to number of outgoing flavours. |
---|
3304 | sigma = nQuarkNew * sigS / (16. * M_PI * sH2); |
---|
3305 | |
---|
3306 | } |
---|
3307 | |
---|
3308 | //-------------------------------------------------------------------------- |
---|
3309 | |
---|
3310 | // Select identity, colour and anticolour. |
---|
3311 | |
---|
3312 | void Sigma2qqbar2LEDqqbarNew::setIdColAcol() { |
---|
3313 | |
---|
3314 | // Set outgoing flavours ones. |
---|
3315 | id3 = (id1 > 0) ? idNew : -idNew; |
---|
3316 | setId( id1, id2, id3, -id3); |
---|
3317 | |
---|
3318 | // Colour flow topologies. Swap when antiquarks. |
---|
3319 | setColAcol( 1, 0, 0, 2, 1, 0, 0, 2); |
---|
3320 | if (id1 < 0) swapColAcol(); |
---|
3321 | |
---|
3322 | } |
---|
3323 | |
---|
3324 | //========================================================================== |
---|
3325 | |
---|
3326 | } // end namespace Pythia8 |
---|