1 | // |
---|
2 | // ******************************************************************** |
---|
3 | // * License and Disclaimer * |
---|
4 | // * * |
---|
5 | // * The Geant4 software is copyright of the Copyright Holders of * |
---|
6 | // * the Geant4 Collaboration. It is provided under the terms and * |
---|
7 | // * conditions of the Geant4 Software License, included in the file * |
---|
8 | // * LICENSE and available at http://cern.ch/geant4/license . These * |
---|
9 | // * include a list of copyright holders. * |
---|
10 | // * * |
---|
11 | // * Neither the authors of this software system, nor their employing * |
---|
12 | // * institutes,nor the agencies providing financial support for this * |
---|
13 | // * work make any representation or warranty, express or implied, * |
---|
14 | // * regarding this software system or assume any liability for its * |
---|
15 | // * use. Please see the license in the file LICENSE and URL above * |
---|
16 | // * for the full disclaimer and the limitation of liability. * |
---|
17 | // * * |
---|
18 | // * This code implementation is the result of the scientific and * |
---|
19 | // * technical work of the GEANT4 collaboration. * |
---|
20 | // * By using, copying, modifying or distributing the software (or * |
---|
21 | // * any work based on the software) you agree to acknowledge its * |
---|
22 | // * use in resulting scientific publications, and indicate your * |
---|
23 | // * acceptance of all terms of the Geant4 Software license. * |
---|
24 | // ******************************************************************** |
---|
25 | // |
---|
26 | // $Id: G4PreCompoundHe3.cc,v 1.7 2010/08/28 15:16:55 vnivanch Exp $ |
---|
27 | // GEANT4 tag $Name: geant4-09-03-ref-09 $ |
---|
28 | // |
---|
29 | // ------------------------------------------------------------------- |
---|
30 | // |
---|
31 | // GEANT4 Class file |
---|
32 | // |
---|
33 | // |
---|
34 | // File name: G4PreCompoundHe3 |
---|
35 | // |
---|
36 | // Author: V.Lara |
---|
37 | // |
---|
38 | // Modified: |
---|
39 | // 21.08.2008 J. M. Quesada add choice of options |
---|
40 | // 20.08.2010 V.Ivanchenko added G4Pow and G4PreCompoundParameters pointers |
---|
41 | // use int Z and A and cleanup |
---|
42 | // |
---|
43 | |
---|
44 | #include "G4PreCompoundHe3.hh" |
---|
45 | #include "G4He3.hh" |
---|
46 | |
---|
47 | G4PreCompoundHe3::G4PreCompoundHe3() |
---|
48 | : G4PreCompoundIon(G4He3::He3(), &theHe3CoulombBarrier) |
---|
49 | {} |
---|
50 | |
---|
51 | G4PreCompoundHe3::~G4PreCompoundHe3() |
---|
52 | {} |
---|
53 | |
---|
54 | G4double G4PreCompoundHe3::FactorialFactor(G4int N, G4int P) |
---|
55 | { |
---|
56 | return G4double((N-3)*(P-2)*(N-2)*(P-1)*(N-1)*P)/6.0; |
---|
57 | } |
---|
58 | |
---|
59 | G4double G4PreCompoundHe3::CoalescenceFactor(G4int A) |
---|
60 | { |
---|
61 | return 243.0/G4double(A*A); |
---|
62 | } |
---|
63 | |
---|
64 | G4double G4PreCompoundHe3::GetRj(G4int nParticles, G4int nCharged) |
---|
65 | { |
---|
66 | G4double rj = 0.0; |
---|
67 | if(nCharged >=2 && (nParticles-nCharged) >= 1) { |
---|
68 | G4double denominator = G4double(nParticles*(nParticles-1)*(nParticles-2)); |
---|
69 | rj = G4double(3*nCharged*(nCharged-1)*(nParticles-nCharged))/denominator; |
---|
70 | } |
---|
71 | return rj; |
---|
72 | } |
---|
73 | |
---|
74 | //////////////////////////////////////////////////////////////////////////////// |
---|
75 | //J. M. Quesada (Dec 2007-June 2008): New inverse reaction cross sections |
---|
76 | //OPT=0 Dostrovski's parameterization |
---|
77 | //OPT=1,2 Chatterjee's paramaterization |
---|
78 | //OPT=3,4 Kalbach's parameterization |
---|
79 | // |
---|
80 | G4double G4PreCompoundHe3::CrossSection(G4double K) |
---|
81 | { |
---|
82 | ResidualA = GetRestA(); |
---|
83 | ResidualZ = GetRestZ(); |
---|
84 | theA = GetA(); |
---|
85 | theZ = GetZ(); |
---|
86 | ResidualAthrd = ResidualA13(); |
---|
87 | FragmentA = theA + ResidualA; |
---|
88 | FragmentAthrd = g4pow->Z13(FragmentA); |
---|
89 | |
---|
90 | if (OPTxs==0) return GetOpt0( K); |
---|
91 | else if( OPTxs==1 || OPTxs==2) return GetOpt12( K); |
---|
92 | else if (OPTxs==3 || OPTxs==4) return GetOpt34( K); |
---|
93 | else{ |
---|
94 | std::ostringstream errOs; |
---|
95 | errOs << "BAD He3 CROSS SECTION OPTION !!" <<G4endl; |
---|
96 | throw G4HadronicException(__FILE__, __LINE__, errOs.str()); |
---|
97 | return 0.; |
---|
98 | } |
---|
99 | } |
---|
100 | |
---|
101 | G4double G4PreCompoundHe3::GetAlpha() |
---|
102 | { |
---|
103 | G4double C = 0.0; |
---|
104 | G4int aZ = theZ + ResidualZ; |
---|
105 | if (aZ <= 30) |
---|
106 | { |
---|
107 | C = 0.10; |
---|
108 | } |
---|
109 | else if (aZ <= 50) |
---|
110 | { |
---|
111 | C = 0.1 - (aZ - 30)*0.001; |
---|
112 | } |
---|
113 | else if (aZ < 70) |
---|
114 | { |
---|
115 | C = 0.08 - (aZ - 50)*0.001; |
---|
116 | } |
---|
117 | else |
---|
118 | { |
---|
119 | C = 0.06; |
---|
120 | } |
---|
121 | return 1.0 + C*(4.0/3.0); |
---|
122 | } |
---|
123 | |
---|
124 | //********************* OPT=1,2 : Chatterjee's cross section ***************** |
---|
125 | //(fitting to cross section from Bechetti & Greenles OM potential) |
---|
126 | |
---|
127 | G4double G4PreCompoundHe3::GetOpt12(const G4double K) |
---|
128 | { |
---|
129 | G4double Kc = K; |
---|
130 | |
---|
131 | // JMQ xsec is set constat above limit of validity |
---|
132 | if (K > 50*MeV) { Kc = 50*MeV; } |
---|
133 | |
---|
134 | G4double landa ,mu ,nu ,p , Ec,q,r,ji,xs; |
---|
135 | |
---|
136 | G4double p0 = -3.06; |
---|
137 | G4double p1 = 278.5; |
---|
138 | G4double p2 = -1389.; |
---|
139 | G4double landa0 = -0.00535; |
---|
140 | G4double landa1 = -11.16; |
---|
141 | G4double mu0 = 555.5; |
---|
142 | G4double mu1 = 0.40; |
---|
143 | G4double nu0 = 687.4; |
---|
144 | G4double nu1 = -476.3; |
---|
145 | G4double nu2 = 0.509; |
---|
146 | G4double delta=1.2; |
---|
147 | |
---|
148 | Ec = 1.44*theZ*ResidualZ/(1.5*ResidualAthrd+delta); |
---|
149 | p = p0 + p1/Ec + p2/(Ec*Ec); |
---|
150 | landa = landa0*ResidualA + landa1; |
---|
151 | |
---|
152 | G4double resmu1 = g4pow->powZ(ResidualA,mu1); |
---|
153 | mu = mu0*resmu1; |
---|
154 | nu = resmu1*(nu0 + nu1*Ec + nu2*(Ec*Ec)); |
---|
155 | q = landa - nu/(Ec*Ec) - 2*p*Ec; |
---|
156 | r = mu + 2*nu/Ec + p*(Ec*Ec); |
---|
157 | |
---|
158 | ji=std::max(Kc,Ec); |
---|
159 | if(Kc < Ec) { xs = p*Kc*Kc + q*Kc + r;} |
---|
160 | else {xs = p*(Kc - ji)*(Kc - ji) + landa*Kc + mu + nu*(2 - Kc/ji)/ji ;} |
---|
161 | |
---|
162 | if (xs <0.0) {xs=0.0;} |
---|
163 | |
---|
164 | return xs; |
---|
165 | |
---|
166 | } |
---|
167 | |
---|
168 | // *********** OPT=3,4 : Kalbach's cross sections (from PRECO code)************* |
---|
169 | G4double G4PreCompoundHe3::GetOpt34(const G4double K) |
---|
170 | //c ** 3he from o.m. of gibson et al |
---|
171 | { |
---|
172 | G4double landa, mu, nu, p , signor(1.),sig; |
---|
173 | G4double ec,ecsq,xnulam,etest(0.),a; |
---|
174 | G4double b,ecut,cut,ecut2,geom,elab; |
---|
175 | |
---|
176 | G4double flow = 1.e-18; |
---|
177 | G4double spill= 1.e+18; |
---|
178 | |
---|
179 | G4double p0 = -2.88; |
---|
180 | G4double p1 = 205.6; |
---|
181 | G4double p2 = -1487.; |
---|
182 | G4double landa0 = 0.00459; |
---|
183 | G4double landa1 = -8.93; |
---|
184 | G4double mu0 = 611.2; |
---|
185 | G4double mu1 = 0.35; |
---|
186 | G4double nu0 = 473.8; |
---|
187 | G4double nu1 = -468.2; |
---|
188 | G4double nu2 = -2.225; |
---|
189 | |
---|
190 | G4double ra=0.80; |
---|
191 | |
---|
192 | //JMQ 13/02/09 increase of reduced radius to lower the barrier |
---|
193 | // ec = 1.44 * theZ * ResidualZ / (1.5*ResidualAthrd+ra); |
---|
194 | ec = 1.44 * theZ * ResidualZ / (1.7*ResidualAthrd+ra); |
---|
195 | ecsq = ec * ec; |
---|
196 | p = p0 + p1/ec + p2/ecsq; |
---|
197 | landa = landa0*ResidualA + landa1; |
---|
198 | a = g4pow->powZ(ResidualA,mu1); |
---|
199 | mu = mu0 * a; |
---|
200 | nu = a* (nu0+nu1*ec+nu2*ecsq); |
---|
201 | xnulam = nu / landa; |
---|
202 | if (xnulam > spill) { xnulam=0.; } |
---|
203 | if (xnulam >= flow) { etest = 1.2 *std::sqrt(xnulam); } |
---|
204 | |
---|
205 | a = -2.*p*ec + landa - nu/ecsq; |
---|
206 | b = p*ecsq + mu + 2.*nu/ec; |
---|
207 | ecut = 0.; |
---|
208 | cut = a*a - 4.*p*b; |
---|
209 | if (cut > 0.) ecut = std::sqrt(cut); |
---|
210 | ecut = (ecut-a) / (p+p); |
---|
211 | ecut2 = ecut; |
---|
212 | //JMQ 290310 for avoiding unphysical increase below minimum (at ecut) |
---|
213 | // ecut<0 means that there is no cut with energy axis, i.e. xs is set |
---|
214 | // to 0 bellow minimum |
---|
215 | // if (cut < 0.) ecut2 = ecut - 2.; |
---|
216 | if (cut < 0.) { ecut2 = ecut; } |
---|
217 | elab = K * FragmentA / ResidualA; |
---|
218 | sig = 0.; |
---|
219 | |
---|
220 | if (elab <= ec) { //start for E<Ec |
---|
221 | if (elab > ecut2) { sig = (p*elab*elab+a*elab+b) * signor; } |
---|
222 | } //end for E<Ec |
---|
223 | else { //start for E>Ec |
---|
224 | sig = (landa*elab+mu+nu/elab) * signor; |
---|
225 | geom = 0.; |
---|
226 | if (xnulam < flow || elab < etest) { return sig; } |
---|
227 | geom = std::sqrt(theA*K); |
---|
228 | geom = 1.23*ResidualAthrd + ra + 4.573/geom; |
---|
229 | geom = 31.416 * geom * geom; |
---|
230 | sig = std::max(geom,sig); |
---|
231 | } //end for E>Ec |
---|
232 | return sig; |
---|
233 | |
---|
234 | } |
---|