1 | <!-- ******************************************************** --> |
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2 | <!-- --> |
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3 | <!-- [History] --> |
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4 | <!-- Converted to DocBook: Katsuya Amako, Aug-2006 --> |
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5 | <!-- Changed by: Katsuya Amako, 21-Sep-1998 --> |
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6 | <!-- Proof read by: Joe Chuma, 30-Jun-1999 --> |
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7 | <!-- Changed by: Dennis Wright, 29-Nov-2001 --> |
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8 | <!-- Changed by: Makoto Asai, 30-Nov-2005 --> |
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9 | <!-- --> |
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10 | <!-- ******************************************************** --> |
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11 | |
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12 | <!-- ******************* Section (Level#1) ****************** --> |
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13 | <sect1 id="sect.Hits"> |
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14 | <title> |
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15 | Hits |
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16 | </title> |
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17 | |
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18 | |
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19 | <!-- ******************* Section (Level#2) ****************** --> |
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20 | <sect2 id="sect.Hits.Hit"> |
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21 | <title> |
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22 | Hit |
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23 | </title> |
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24 | |
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25 | <para> |
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26 | A hit is a snapshot of the physical interaction of a track in the |
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27 | sensitive region of a detector. In it you can store information |
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28 | associated with a <emphasis>G4Step</emphasis> object. This information can be |
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29 | |
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30 | <itemizedlist spacing="compact"> |
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31 | <listitem><para> |
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32 | the position and time of the step, |
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33 | </para></listitem> |
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34 | <listitem><para> |
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35 | the momentum and energy of the track, |
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36 | </para></listitem> |
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37 | <listitem><para> |
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38 | the energy deposition of the step, |
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39 | </para></listitem> |
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40 | <listitem><para> |
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41 | geometrical information, |
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42 | </para></listitem> |
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43 | </itemizedlist> |
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44 | |
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45 | or any combination of the above. |
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46 | </para> |
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47 | |
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48 | <!-- ******* Bridgehead ******* --> |
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49 | <bridgehead renderas='sect4'> |
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50 | G4VHit |
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51 | </bridgehead> |
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52 | |
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53 | <para> |
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54 | <emphasis>G4VHit</emphasis> is an abstract base class which represents a hit. |
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55 | You must inherit this base class and derive your own concrete hit |
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56 | class(es). The member data of your concrete hit class can be, and |
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57 | should be, your choice. |
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58 | </para> |
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59 | |
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60 | <para> |
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61 | <emphasis>G4VHit</emphasis> has two virtual methods, <literal>Draw()</literal> and |
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62 | <literal>Print()</literal>. To draw or print out your concrete hits, these |
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63 | methods should be implemented. How to define the drawing method is |
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64 | described in <xref linkend="sect.VisPlylMrkTxt" />. |
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65 | </para> |
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66 | |
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67 | <!-- ******* Bridgehead ******* --> |
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68 | <bridgehead renderas='sect4'> |
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69 | G4THitsCollection |
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70 | </bridgehead> |
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71 | |
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72 | <para> |
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73 | <emphasis>G4VHit</emphasis> is an abstract class from which you derive your |
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74 | own concrete classes. During the processing of a given event, |
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75 | represented by a <emphasis>G4Event</emphasis> object, many objects of the hit |
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76 | class will be produced, collected and associated with the event. |
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77 | Therefore, for each concrete hit class you must also prepare a |
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78 | concrete class derived from <emphasis>G4VHitsCollection</emphasis>, an abstract |
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79 | class which represents a vector collection of user defined |
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80 | hits. |
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81 | </para> |
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82 | |
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83 | <para> |
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84 | <emphasis>G4THitsCollection</emphasis> is a template class derived from |
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85 | <emphasis>G4VHitsCollection</emphasis>, and the concrete hit collection class of |
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86 | a particular <emphasis>G4VHit</emphasis> concrete class can be instantiated from |
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87 | this template class. Each object of a hit collection must have a |
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88 | unique name for each event. |
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89 | </para> |
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90 | |
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91 | <para> |
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92 | <emphasis>G4Event</emphasis> has a <emphasis>G4HCofThisEvent</emphasis> class |
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93 | object, that is a container class of collections of hits. Hit collections are |
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94 | stored by their pointers, whose type is that of the base class. |
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95 | </para> |
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96 | |
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97 | <!-- ******* Bridgehead ******* --> |
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98 | <bridgehead renderas='sect4'> |
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99 | An example of a concrete hit class |
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100 | </bridgehead> |
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101 | |
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102 | <para> |
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103 | <xref linkend="programlist_Hits_1" /> shows an example of a concrete hit class. |
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104 | |
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105 | <example id="programlist_Hits_1"> |
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106 | <title> |
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107 | An example of a concrete hit class. |
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108 | </title> |
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109 | |
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110 | <programlisting> |
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111 | #ifndef ExN04TrackerHit_h |
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112 | #define ExN04TrackerHit_h 1 |
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113 | |
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114 | #include "G4VHit.hh" |
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115 | #include "G4THitsCollection.hh" |
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116 | #include "G4Allocator.hh" |
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117 | #include "G4ThreeVector.hh" |
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118 | |
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119 | class ExN04TrackerHit : public G4VHit |
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120 | { |
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121 | public: |
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122 | |
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123 | ExN04TrackerHit(); |
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124 | ~ExN04TrackerHit(); |
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125 | ExN04TrackerHit(const ExN04TrackerHit &right); |
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126 | const ExN04TrackerHit& operator=(const ExN04TrackerHit &right); |
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127 | int operator==(const ExN04TrackerHit &right) const; |
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128 | |
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129 | inline void * operator new(size_t); |
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130 | inline void operator delete(void *aHit); |
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131 | |
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132 | void Draw() const; |
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133 | void Print() const; |
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134 | |
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135 | private: |
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136 | G4double edep; |
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137 | G4ThreeVector pos; |
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138 | |
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139 | public: |
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140 | inline void SetEdep(G4double de) |
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141 | { edep = de; } |
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142 | inline G4double GetEdep() const |
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143 | { return edep; } |
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144 | inline void SetPos(G4ThreeVector xyz) |
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145 | { pos = xyz; } |
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146 | inline G4ThreeVector GetPos() const |
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147 | { return pos; } |
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148 | |
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149 | }; |
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150 | |
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151 | typedef G4THitsCollection<ExN04TrackerHit> ExN04TrackerHitsCollection; |
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152 | |
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153 | extern G4Allocator<ExN04TrackerHit> ExN04TrackerHitAllocator; |
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154 | |
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155 | inline void* ExN04TrackerHit::operator new(size_t) |
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156 | { |
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157 | void *aHit; |
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158 | aHit = (void *) ExN04TrackerHitAllocator.MallocSingle(); |
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159 | return aHit; |
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160 | } |
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161 | |
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162 | inline void ExN04TrackerHit::operator delete(void *aHit) |
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163 | { |
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164 | ExN04TrackerHitAllocator.FreeSingle((ExN04TrackerHit*) aHit); |
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165 | } |
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166 | |
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167 | #endif |
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168 | </programlisting> |
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169 | </example> |
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170 | </para> |
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171 | |
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172 | <para> |
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173 | <emphasis>G4Allocator</emphasis> is a class for fast allocation of objects to |
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174 | the heap through the paging mechanism. For details of |
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175 | <emphasis>G4Allocator</emphasis>, refer to <xref linkend="sect.GeneManage" />. |
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176 | Use of <emphasis>G4Allocator</emphasis> |
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177 | is not mandatory, but it is recommended, especially for users who |
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178 | are not familiar with the C++ memory allocation mechanism or |
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179 | alternative tools of memory allocation. On the other hand, note |
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180 | that <emphasis>G4Allocator</emphasis> is to be used |
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181 | <emphasis role="bold">only</emphasis> for the concrete |
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182 | class that is <emphasis role="bold">not</emphasis> used as a base |
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183 | class of any other classes. |
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184 | For example, do <emphasis role="bold">not</emphasis> use the |
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185 | <emphasis>G4Trajectory</emphasis> class as a |
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186 | base class for a customized trajectory class, since |
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187 | <emphasis>G4Trajectory</emphasis> uses <emphasis>G4Allocator</emphasis>. |
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188 | </para> |
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189 | |
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190 | <!-- ******* Bridgehead ******* --> |
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191 | <bridgehead renderas='sect4'> |
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192 | G4THitsMap |
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193 | </bridgehead> |
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194 | |
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195 | <para> |
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196 | <emphasis>G4THitsMap</emphasis> is an alternative to |
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197 | <emphasis>G4THitsCollection</emphasis>. |
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198 | <emphasis>G4THitsMap</emphasis> does not demand <emphasis>G4VHit</emphasis>, |
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199 | but instead any variable which can be mapped with an integer key. Typically the key |
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200 | is a copy number of the volume, and the mapped value could for |
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201 | example be a double, such as the energy deposition in a volume. |
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202 | <emphasis>G4THitsMap</emphasis> is convenient for applications which do not need |
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203 | to output event-by-event data but instead just accumulate them. All |
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204 | the <emphasis>G4VPrimitiveScorer</emphasis> classes discussed in |
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205 | <xref linkend="sect.Hits.G4Multi" /> use <emphasis>G4THitsMap</emphasis>. |
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206 | </para> |
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207 | |
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208 | <para> |
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209 | <emphasis>G4THitsMap</emphasis> is derived from the |
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210 | <emphasis>G4VHitsCollection</emphasis> |
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211 | abstract base class and all objects of this class are also stored |
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212 | in <emphasis>G4HCofThisEvent</emphasis> at the end of an event. How to access a |
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213 | <emphasis>G4THitsMap</emphasis> object is discussed in the |
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214 | following section (<xref linkend="sect.Hits.G4Multi" />). |
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215 | </para> |
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216 | |
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217 | </sect2> |
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218 | |
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219 | |
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220 | <!-- ******************* Section (Level#2) ****************** --> |
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221 | <sect2 id="sect.Hits.SensDet"> |
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222 | <title> |
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223 | Sensitive detector |
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224 | </title> |
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225 | |
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226 | <!-- ******* Bridgehead ******* --> |
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227 | <bridgehead renderas='sect4'> |
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228 | G4VSensitiveDetector |
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229 | </bridgehead> |
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230 | |
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231 | <para> |
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232 | <emphasis>G4VSensitiveDetector</emphasis> is an abstract base class which |
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233 | represents a detector. The principal mandate of a sensitive |
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234 | detector is the construction of hit objects using information from |
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235 | steps along a particle track. The <literal>ProcessHits()</literal> method of |
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236 | <emphasis>G4VSensitiveDetector</emphasis> performs this task using |
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237 | <emphasis>G4Step</emphasis> |
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238 | objects as input. In the case of a "Readout" geometry (see |
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239 | <xref linkend="sect.Hits.ReadGeom" />), objects of the |
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240 | <emphasis>G4TouchableHistory</emphasis> class may be used as an optional input. |
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241 | </para> |
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242 | |
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243 | <para> |
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244 | Your concrete detector class should be instantiated with the |
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245 | unique name of your detector. The name can be associated with one |
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246 | or more global names with "/" as a delimiter for categorizing your |
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247 | detectors. For example |
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248 | |
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249 | <informalexample> |
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250 | <programlisting> |
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251 | myEMcal = new MyEMcal("/myDet/myCal/myEMcal"); |
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252 | </programlisting> |
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253 | </informalexample> |
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254 | |
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255 | where <literal>myEMcal</literal> is the name of your detector. The pointer to |
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256 | your sensitive detector must be set to one or more |
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257 | <emphasis>G4LogicalVolume</emphasis> objects to set the sensitivity of these |
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258 | volumes. The pointer should also be registered to |
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259 | <emphasis>G4SDManager</emphasis>, as described in |
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260 | <xref linkend="sect.Hits.G4SDMan" />. |
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261 | </para> |
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262 | |
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263 | <para> |
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264 | <emphasis>G4VSensitiveDetector</emphasis> has three major virtual methods. |
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265 | |
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266 | <variablelist><title></title> |
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267 | <varlistentry> |
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268 | <term> |
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269 | <literal>ProcessHits()</literal> |
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270 | </term> |
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271 | <listitem><para> |
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272 | This method is invoked by <emphasis>G4SteppingManager</emphasis> when a step |
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273 | is composed in the <emphasis>G4LogicalVolume</emphasis> which has the pointer |
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274 | to this sensitive detector. The first argument of this method is a |
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275 | <emphasis>G4Step</emphasis> object of the current step. The second argument is a |
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276 | <emphasis>G4TouchableHistory</emphasis> object for the ``Readout geometry'' |
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277 | described in the next section. The second argument is <literal>NULL</literal> |
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278 | if ``Readout geometry'' is not assigned to this sensitive detector. |
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279 | In this method, one or more <emphasis>G4VHit</emphasis> objects should be |
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280 | constructed if the current step is meaningful for your |
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281 | detector. |
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282 | </para></listitem> |
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283 | </varlistentry> |
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284 | <varlistentry> |
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285 | <term> |
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286 | <literal>Initialize()</literal> |
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287 | </term> |
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288 | <listitem><para> |
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289 | This method is invoked at the beginning of each event. The |
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290 | argument of this method is an object of the <emphasis>G4HCofThisEvent</emphasis> |
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291 | class. Hit collections, where hits produced in this particular |
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292 | event are stored, can be associated with the <emphasis>G4HCofThisEvent</emphasis> |
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293 | object in this method. The hit collections associated with the |
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294 | <emphasis>G4HCofThisEvent</emphasis> object during this method can be used for |
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295 | ``during the event processing'' digitization. |
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296 | </para></listitem> |
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297 | </varlistentry> |
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298 | <varlistentry> |
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299 | <term> |
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300 | <literal>EndOfEvent()</literal> |
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301 | </term> |
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302 | <listitem><para> |
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303 | This method is invoked at the end of each event. The argument |
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304 | of this method is the same object as the previous method. Hit |
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305 | collections occasionally created in your sensitive detector can be |
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306 | associated with the <emphasis>G4HCofThisEvent</emphasis> object. |
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307 | </para></listitem> |
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308 | </varlistentry> |
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309 | </variablelist> |
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310 | </para> |
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311 | |
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312 | </sect2> |
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313 | |
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314 | |
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315 | <!-- ******************* Section (Level#2) ****************** --> |
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316 | <sect2 id="sect.Hits.ReadGeom"> |
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317 | <title> |
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318 | Readout geometry |
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319 | </title> |
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320 | |
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321 | <para> |
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322 | This section describes how a ``Readout geometry'' can be defined. A |
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323 | Readout geometry is a virtual, parallel geometry for obtaining the |
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324 | channel number. |
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325 | </para> |
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326 | |
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327 | <para> |
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328 | As an example, the accordion calorimeter of <emphasis role="bold">ATLAS</emphasis> |
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329 | has a complicated tracking geometry, however the readout can be done by |
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330 | simple cylindrical sectors divided by theta, phi, and depth. Tracks |
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331 | will be traced in the tracking geometry, the ``real'' one, and the |
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332 | sensitive detector will have its own readout geometry Geant4 will |
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333 | message to find to which ``readout'' cell the current hit |
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334 | belongs. |
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335 | |
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336 | <figure id="fig.Hits_1"> |
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337 | <title> |
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338 | Association of tracking and readout geometry. |
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339 | </title> |
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340 | <mediaobject> |
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341 | <imageobject role="fo"> |
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342 | <imagedata fileref="./AllResources/Detector/hit.src/RO.jpg" |
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343 | format="JPG" contentwidth="10.0cm" align="center" /> |
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344 | </imageobject> |
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345 | <imageobject role="html"> |
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346 | <imagedata fileref="./AllResources/Detector/hit.src/RO.jpg" |
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347 | format="JPG" align="center" /> |
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348 | </imageobject> |
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349 | </mediaobject> |
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350 | </figure> |
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351 | </para> |
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352 | |
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353 | <para> |
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354 | <xref linkend="fig.Hits_1" /> shows how this association is done in Geant4. |
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355 | The first step is to associate a sensitive detector to a volume of the |
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356 | tracking geometry, in the usual way (see |
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357 | <xref linkend="sect.Hits.SensDet" />). The next step is to associate your |
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358 | <emphasis>G4VReadoutGeometry</emphasis> object to the sensitive detector. |
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359 | </para> |
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360 | |
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361 | <para> |
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362 | At tracking time, the base class <emphasis>G4VReadoutGeometry</emphasis> will |
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363 | provide to your sensitive detector code the |
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364 | <emphasis>G4TouchableHistory</emphasis> in the Readout geometry at the beginning |
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365 | of the step position (position of <emphasis>PreStepPoint</emphasis> of |
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366 | <emphasis>G4Step</emphasis>) and at this position only. |
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367 | </para> |
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368 | |
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369 | <para> |
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370 | This <emphasis>G4TouchableHistory</emphasis> is given to your sensitive |
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371 | detector code through the <emphasis>G4VSensitiveDetector</emphasis> virtual |
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372 | method: |
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373 | |
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374 | <informalexample> |
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375 | <programlisting> |
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376 | G4bool processHits(G4Step* aStep, G4TouchableHistory* ROhist); |
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377 | </programlisting> |
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378 | </informalexample> |
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379 | |
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380 | by the <literal>ROhist</literal> argument. |
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381 | </para> |
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382 | |
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383 | <para> |
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384 | Thus, you will be able to use information from both the |
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385 | <emphasis>G4Step</emphasis> and the <emphasis>G4TouchableHistory</emphasis> |
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386 | coming from your |
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387 | Readout geometry. Note that since the association is done through a |
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388 | sensitive detector object, it is perfectly possible to have several |
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389 | Readout geometries in parallel. |
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390 | </para> |
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391 | |
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392 | |
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393 | <!-- ******* Bridgehead ******* --> |
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394 | <bridgehead renderas='sect4'> |
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395 | Definition of a virtual geometry setup |
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396 | </bridgehead> |
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397 | |
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398 | <para> |
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399 | The base class for the implementation of a Readout geometry is |
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400 | <emphasis>G4VReadoutGeometry</emphasis>. This class has a single pure virtual |
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401 | protected method: |
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402 | |
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403 | <informalexample> |
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404 | <programlisting> |
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405 | virtual G4VPhysicalVolume* build() = 0; |
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406 | </programlisting> |
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407 | </informalexample> |
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408 | |
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409 | which you must override in your concrete class. The |
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410 | <emphasis>G4VPhysicalVolume</emphasis> pointer you will have to return is of the |
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411 | physical world of the Readout geometry. |
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412 | </para> |
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413 | |
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414 | <para> |
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415 | The step by step procedure for constructing a Readout geometry is: |
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416 | |
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417 | <itemizedlist spacing="compact"> |
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418 | <listitem><para> |
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419 | inherit from <emphasis>G4VReadoutGeometry</emphasis> to define a |
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420 | <emphasis>MyROGeom</emphasis> class; |
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421 | </para></listitem> |
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422 | <listitem><para> |
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423 | implement the Readout geometry in the <literal>build()</literal> method, |
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424 | returning the physical world of this geometry. |
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425 | <para> |
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426 | The world is specified in the same way as for the detector |
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427 | construction: a physical volume with no mother. The axis system of |
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428 | this world is the same as the one of the world for tracking. |
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429 | </para> |
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430 | <para> |
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431 | In this geometry you need to declare the sensitive parts in the |
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432 | same way as in the tracking geometry: by setting a |
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433 | non-<literal>NULL</literal> <emphasis>G4VSensitiveDetector</emphasis> |
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434 | pointer in, say, the |
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435 | relevant <emphasis>G4LogicalVolume</emphasis> objects. This sensitive class needs |
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436 | to be there, but will not be used. |
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437 | </para> |
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438 | <para> |
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439 | You will also need to assign well defined materials to the |
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440 | volumes you place in this geometry, but these materials are |
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441 | irrelevant since they will not be seen by the tracking. It is |
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442 | foreseen to allow the setting of a <literal>NULL</literal> pointer in this |
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443 | case of the parallel geometry. |
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444 | </para> |
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445 | </para></listitem> |
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446 | <listitem><para> |
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447 | in the <literal>construct()</literal> method of your concrete |
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448 | <emphasis>G4VUserDetectorConstruction</emphasis> class: |
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449 | <para> |
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450 | <itemizedlist spacing="compact"> |
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451 | <listitem><para> |
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452 | instantiate your Readout geometry: |
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453 | <informalexample> |
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454 | <programlisting> |
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455 | MyROGeom* ROgeom = new MyROGeom("ROName"); |
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456 | </programlisting> |
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457 | </informalexample> |
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458 | </para></listitem> |
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459 | <listitem><para> |
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460 | build it: |
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461 | <informalexample> |
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462 | <programlisting> |
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463 | ROgeom->buildROGeometry(); |
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464 | </programlisting> |
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465 | </informalexample> |
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466 | That will invoke your <literal>build()</literal> method. |
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467 | </para></listitem> |
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468 | <listitem><para> |
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469 | Instantiate the sensitive detector which will receive the |
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470 | <literal>ROGeom</literal> pointer, <literal>MySensitive</literal>, |
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471 | and add this sensitive to the <emphasis>G4SDManager</emphasis>. |
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472 | Associate this sensitive to |
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473 | the volume(s) of the tracking geometry as usual. |
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474 | </para></listitem> |
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475 | <listitem><para> |
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476 | Associate the sensitive to the Readout geometry: |
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477 | <informalexample> |
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478 | <programlisting> |
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479 | MySensitive->SetROgeometry(ROgeom); |
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480 | </programlisting> |
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481 | </informalexample> |
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482 | </para></listitem> |
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483 | </itemizedlist> |
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484 | </para> |
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485 | </para></listitem> |
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486 | </itemizedlist> |
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487 | </para> |
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488 | |
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489 | </sect2> |
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490 | |
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491 | |
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492 | <!-- ******************* Section (Level#2) ****************** --> |
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493 | <sect2 id="sect.Hits.G4SDMan"> |
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494 | <title> |
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495 | G4SDManager |
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496 | </title> |
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497 | |
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498 | <para> |
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499 | <emphasis>G4SDManager</emphasis> is the singleton manager class for sensitive |
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500 | detectors. |
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501 | </para> |
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502 | |
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503 | <!-- ******* Bridgehead ******* --> |
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504 | <bridgehead renderas='sect4'> |
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505 | Activation/inactivation of sensitive detectors |
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506 | </bridgehead> |
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507 | |
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508 | <para> |
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509 | The user interface commands <literal>activate</literal> and |
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510 | <literal>inactivate</literal> are available to control your sensitive |
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511 | detectors. For example: |
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512 | |
---|
513 | <informalexample> |
---|
514 | <programlisting> |
---|
515 | /hits/activate detector_name |
---|
516 | /hits/inactivate detector_name |
---|
517 | </programlisting> |
---|
518 | </informalexample> |
---|
519 | |
---|
520 | where <literal>detector_name</literal> can be the detector name or the |
---|
521 | category name. |
---|
522 | </para> |
---|
523 | |
---|
524 | <para> |
---|
525 | For example, if your EM calorimeter is named |
---|
526 | |
---|
527 | <informalexample> |
---|
528 | <programlisting> |
---|
529 | /myDet/myCal/myEMcal |
---|
530 | /hits/inactivate myCal |
---|
531 | </programlisting> |
---|
532 | </informalexample> |
---|
533 | |
---|
534 | will inactivate all detectors belonging to the <literal>myCal</literal> |
---|
535 | category. |
---|
536 | </para> |
---|
537 | |
---|
538 | <!-- ******* Bridgehead ******* --> |
---|
539 | <bridgehead renderas='sect4'> |
---|
540 | Access to the hit collections |
---|
541 | </bridgehead> |
---|
542 | |
---|
543 | |
---|
544 | <para>Hit collections are accessed for various cases. |
---|
545 | |
---|
546 | <itemizedlist spacing="compact"> |
---|
547 | <listitem><para> |
---|
548 | Digitization |
---|
549 | </para></listitem> |
---|
550 | <listitem><para> |
---|
551 | Event filtering in <emphasis>G4VUserStackingAction</emphasis> |
---|
552 | </para></listitem> |
---|
553 | <listitem><para> |
---|
554 | ``End of event'' simple analysis |
---|
555 | </para></listitem> |
---|
556 | <listitem><para> |
---|
557 | Drawing / printing hits |
---|
558 | </para></listitem> |
---|
559 | </itemizedlist> |
---|
560 | </para> |
---|
561 | |
---|
562 | <para> |
---|
563 | The following is an example of how to access the hit collection |
---|
564 | of a particular concrete type: |
---|
565 | |
---|
566 | <informalexample> |
---|
567 | <programlisting> |
---|
568 | G4SDManager* fSDM = G4SDManager::GetSDMpointer(); |
---|
569 | G4RunManager* fRM = G4RunManager::GetRunManager(); |
---|
570 | G4int collectionID = fSDM->GetCollectionID("collection_name"); |
---|
571 | const G4Event* currentEvent = fRM->GetCurrentEvent(); |
---|
572 | G4HCofThisEvent* HCofEvent = currentEvent->GetHCofThisEvent(); |
---|
573 | <emphasis>MyHitsCollection</emphasis>* myCollection = (<emphasis>MyHitsCollection</emphasis>*)(HC0fEvent->GetHC(collectionID)); |
---|
574 | </programlisting> |
---|
575 | </informalexample> |
---|
576 | </para> |
---|
577 | |
---|
578 | </sect2> |
---|
579 | |
---|
580 | |
---|
581 | <!-- ******************* Section (Level#2) ****************** --> |
---|
582 | <sect2 id="sect.Hits.G4Multi"> |
---|
583 | <title> |
---|
584 | <emphasis>G4MultiFunctionalDetector</emphasis> and |
---|
585 | <emphasis>G4VPrimitiveScorer</emphasis> |
---|
586 | </title> |
---|
587 | |
---|
588 | <para> |
---|
589 | <emphasis>G4MultiFunctionalDetector</emphasis> is a concrete class derived from |
---|
590 | <emphasis>G4VSensitiveDetector</emphasis>. Instead of implementing a |
---|
591 | user-specific detector class, <emphasis>G4MultiFunctionalDetector</emphasis> |
---|
592 | allows the user to register <emphasis>G4VPrimitiveScorer</emphasis> classes to |
---|
593 | build up the sensitivity. <emphasis>G4MultiFunctionalDetector</emphasis> should |
---|
594 | be instantiated in the users detector construction with its unique |
---|
595 | name and should be assigned to one or more <emphasis>G4LogicalVolume</emphasis>s. |
---|
596 | </para> |
---|
597 | |
---|
598 | <para> |
---|
599 | <emphasis>G4VPrimitiveScorer</emphasis> is an abstract base class representing |
---|
600 | a class to be registered to <emphasis>G4MultiFunctionalDetector</emphasis> that |
---|
601 | creates a <emphasis>G4THitsMap</emphasis> object of one physics quantity for an |
---|
602 | event. Geant4 provides many concrete primitive scorer classes |
---|
603 | listed in <xref linkend="sect.Hits.G4VPrim" />, and the user can |
---|
604 | also implement his/her own primitive scorers. Each primitive scorer |
---|
605 | object must be instantiated with a name that must be unique among |
---|
606 | primitive scorers registered in a <emphasis>G4MultiFunctionalDetector</emphasis>. |
---|
607 | Please note that a primitive scorer object must <emphasis role="bold">not</emphasis> be |
---|
608 | shared by more than one <emphasis>G4MultiFunctionalDetector</emphasis> |
---|
609 | object. |
---|
610 | </para> |
---|
611 | |
---|
612 | <para>As mentioned in <xref linkend="sect.Hits.Hit" />, |
---|
613 | each <emphasis>G4VPrimitiveScorer</emphasis> generates one |
---|
614 | <emphasis>G4THitsMap</emphasis> object |
---|
615 | per event. The name of the map object is the same as the name of |
---|
616 | the primitive scorer. Each of the concrete primitive scorers listed |
---|
617 | in <xref linkend="sect.Hits.G4VPrim" /> generates a |
---|
618 | <emphasis>G4THitsMap<G4double></emphasis> that maps a |
---|
619 | <emphasis>G4double</emphasis> value |
---|
620 | to its key integer number. By default, the key is taken as the copy |
---|
621 | number of the <emphasis>G4LogicalVolume</emphasis> to which |
---|
622 | <emphasis>G4MultiFunctionalDetector</emphasis> is assigned. In case the logical |
---|
623 | volume is uniquely placed in its mother volume and the mother is |
---|
624 | replicated, the copy number of its mother volume can be taken by |
---|
625 | setting the second argument of the <emphasis>G4VPrimitiveScorer</emphasis> |
---|
626 | constructor, "<emphasis>depth</emphasis>" to 1, i.e. one level up. Furthermore, |
---|
627 | in case the key must consider more than one copy number of a |
---|
628 | different geometry hierarchy, the user can derive his/her own |
---|
629 | primitive scorer from the provided concrete class and implement the |
---|
630 | <emphasis>GetIndex(G4Step*)</emphasis> virtual method to return the unique |
---|
631 | key. |
---|
632 | </para> |
---|
633 | |
---|
634 | <para> |
---|
635 | <xref linkend="programlist_Hits_2" /> shows an example of primitive sensitivity |
---|
636 | class definitions. |
---|
637 | |
---|
638 | <example id="programlist_Hits_2"> |
---|
639 | <title> |
---|
640 | An example of defining primitive sensitivity classes taken from |
---|
641 | <emphasis>ExN07DetectorConstruction</emphasis>. |
---|
642 | </title> |
---|
643 | <programlisting> |
---|
644 | void ExN07DetectorConstruction::SetupDetectors() |
---|
645 | { |
---|
646 | G4String filterName, particleName; |
---|
647 | |
---|
648 | G4SDParticleFilter* gammaFilter = |
---|
649 | new G4SDParticleFilter(filterName="gammaFilter",particleName="gamma"); |
---|
650 | G4SDParticleFilter* electronFilter = |
---|
651 | new G4SDParticleFilter(filterName="electronFilter",particleName="e-"); |
---|
652 | G4SDParticleFilter* positronFilter = |
---|
653 | new G4SDParticleFilter(filterName="positronFilter",particleName="e+"); |
---|
654 | G4SDParticleFilter* epFilter = new G4SDParticleFilter(filterName="epFilter"); |
---|
655 | epFilter->add(particleName="e-"); |
---|
656 | epFilter->add(particleName="e+"); |
---|
657 | |
---|
658 | |
---|
659 | for(G4int i=0;i<3;i++) |
---|
660 | { |
---|
661 | for(G4int j=0;j<2;j++) |
---|
662 | { |
---|
663 | // Loop counter j = 0 : absorber |
---|
664 | // = 1 : gap |
---|
665 | G4String detName = calName[i]; |
---|
666 | if(j==0) |
---|
667 | { detName += "_abs"; } |
---|
668 | else |
---|
669 | { detName += "_gap"; } |
---|
670 | G4MultiFunctionalDetector* det = new G4MultiFunctionalDetector(detName); |
---|
671 | |
---|
672 | // The second argument in each primitive means the "level" of geometrical hierarchy, |
---|
673 | // the copy number of that level is used as the key of the G4THitsMap. |
---|
674 | // For absorber (j = 0), the copy number of its own physical volume is used. |
---|
675 | // For gap (j = 1), the copy number of its mother physical volume is used, since there |
---|
676 | // is only one physical volume of gap is placed with respect to its mother. |
---|
677 | G4VPrimitiveScorer* primitive; |
---|
678 | primitive = new G4PSEnergyDeposit("eDep",j); |
---|
679 | det->RegisterPrimitive(primitive); |
---|
680 | primitive = new G4PSNofSecondary("nGamma",j); |
---|
681 | primitive->SetFilter(gammaFilter); |
---|
682 | det->RegisterPrimitive(primitive); |
---|
683 | primitive = new G4PSNofSecondary("nElectron",j); |
---|
684 | primitive->SetFilter(electronFilter); |
---|
685 | det->RegisterPrimitive(primitive); |
---|
686 | primitive = new G4PSNofSecondary("nPositron",j); |
---|
687 | primitive->SetFilter(positronFilter); |
---|
688 | det->RegisterPrimitive(primitive); |
---|
689 | primitive = new G4PSMinKinEAtGeneration("minEkinGamma",j); |
---|
690 | primitive->SetFilter(gammaFilter); |
---|
691 | det->RegisterPrimitive(primitive); |
---|
692 | primitive = new G4PSMinKinEAtGeneration("minEkinElectron",j); |
---|
693 | primitive->SetFilter(electronFilter); |
---|
694 | det->RegisterPrimitive(primitive); |
---|
695 | primitive = new G4PSMinKinEAtGeneration("minEkinPositron",j); |
---|
696 | primitive->SetFilter(positronFilter); |
---|
697 | det->RegisterPrimitive(primitive); |
---|
698 | primitive = new G4PSTrackLength("trackLength",j); |
---|
699 | primitive->SetFilter(epFilter); |
---|
700 | det->RegisterPrimitive(primitive); |
---|
701 | primitive = new G4PSNofStep("nStep",j); |
---|
702 | primitive->SetFilter(epFilter); |
---|
703 | det->RegisterPrimitive(primitive); |
---|
704 | |
---|
705 | G4SDManager::GetSDMpointer()->AddNewDetector(det); |
---|
706 | if(j==0) |
---|
707 | { layerLogical[i]->SetSensitiveDetector(det); } |
---|
708 | else |
---|
709 | { gapLogical[i]->SetSensitiveDetector(det); } |
---|
710 | } |
---|
711 | } |
---|
712 | } |
---|
713 | </programlisting> |
---|
714 | </example> |
---|
715 | </para> |
---|
716 | |
---|
717 | <para> |
---|
718 | Each <emphasis>G4THitsMap</emphasis> object can be accessed from |
---|
719 | <emphasis>G4HCofThisEvent</emphasis> with a unique collection ID number. This ID |
---|
720 | number can be obtained from <emphasis>G4SDManager::GetCollectionID()</emphasis> |
---|
721 | with a name of <emphasis>G4MultiFunctionalDetector</emphasis> and |
---|
722 | <emphasis>G4VPrimitiveScorer</emphasis> connected with a slush ("/"). |
---|
723 | <emphasis>G4THitsMap</emphasis> has a [] operator taking the key value as an |
---|
724 | argument and returning <emphasis role="bold">the pointer</emphasis> of the value. |
---|
725 | Please note that the [] operator returns |
---|
726 | <emphasis role="bold">the pointer</emphasis> of the value. If |
---|
727 | you get zero from the [] operator, it does <emphasis role="bold">not</emphasis> mean the |
---|
728 | value is zero, but that the provided key does not exist. The value |
---|
729 | itself is accessible with an astarisk ("*"). It is advised to check |
---|
730 | the validity of the returned pointer before accessing the value. |
---|
731 | <emphasis>G4THitsMap</emphasis> also has a += operator in order to accumulate |
---|
732 | event data into run data. <xref linkend="programlist_Hits_3" /> shows the use of |
---|
733 | <emphasis>G4THitsMap</emphasis>. |
---|
734 | |
---|
735 | <example id="programlist_Hits_3"> |
---|
736 | <title> |
---|
737 | An example of accessing to <emphasis>G4THitsMap</emphasis> objects. |
---|
738 | </title> |
---|
739 | |
---|
740 | <programlisting> |
---|
741 | #include "ExN07Run.hh" |
---|
742 | #include "G4Event.hh" |
---|
743 | #include "G4HCofThisEvent.hh" |
---|
744 | #include "G4SDManager.hh" |
---|
745 | |
---|
746 | ExN07Run::ExN07Run() |
---|
747 | { |
---|
748 | G4String detName[6] = {"Calor-A_abs","Calor-A_gap","Calor-B_abs","Calor-B_gap", |
---|
749 | "Calor-C_abs","Calor-C_gap"}; |
---|
750 | G4String primNameSum[6] = {"eDep","nGamma","nElectron","nPositron","trackLength","nStep"}; |
---|
751 | G4String primNameMin[3] = {"minEkinGamma","minEkinElectron","minEkinPositron"}; |
---|
752 | |
---|
753 | G4SDManager* SDMan = G4SDManager::GetSDMpointer(); |
---|
754 | G4String fullName; |
---|
755 | for(size_t i=0;i<6;i++) |
---|
756 | { |
---|
757 | for(size_t j=0;j<6;j++) |
---|
758 | { |
---|
759 | fullName = detName[i]+"/"+primNameSum[j]; |
---|
760 | colIDSum[i][j] = SDMan->GetCollectionID(fullName); |
---|
761 | } |
---|
762 | for(size_t k=0;k<3;k++) |
---|
763 | { |
---|
764 | fullName = detName[i]+"/"+primNameMin[k]; |
---|
765 | colIDMin[i][k] = SDMan->GetCollectionID(fullName); |
---|
766 | } |
---|
767 | } |
---|
768 | } |
---|
769 | |
---|
770 | |
---|
771 | void ExN07Run::RecordEvent(const G4Event* evt) |
---|
772 | { |
---|
773 | G4HCofThisEvent* HCE = evt->GetHCofThisEvent(); |
---|
774 | if(!HCE) return; |
---|
775 | numberOfEvent++; |
---|
776 | for(size_t i=0;i<6;i++) |
---|
777 | { |
---|
778 | for(size_t j=0;j<6;j++) |
---|
779 | { |
---|
780 | G4THitsMap<G4double>* evtMap = (G4THitsMap<G4double>*)(HCE->GetHC(colIDSum[i][j])); |
---|
781 | mapSum[i][j] += *evtMap; |
---|
782 | } |
---|
783 | for(size_t k=0;k<3;k++) |
---|
784 | { |
---|
785 | G4THitsMap<G4double>* evtMap = (G4THitsMap<G4double>*)(HCE->GetHC(colIDMin[i][k])); |
---|
786 | std::map<G4int,G4double*>::iterator itr = evtMap->GetMap()->begin(); |
---|
787 | for(; itr != evtMap->GetMap()->end(); itr++) |
---|
788 | { |
---|
789 | G4int key = (itr->first); |
---|
790 | G4double val = *(itr->second); |
---|
791 | G4double* mapP = mapMin[i][k][key]; |
---|
792 | if( mapP && (val>*mapP) ) continue; |
---|
793 | mapMin[i][k].set(key,val); |
---|
794 | } |
---|
795 | } |
---|
796 | } |
---|
797 | } |
---|
798 | </programlisting> |
---|
799 | </example> |
---|
800 | </para> |
---|
801 | |
---|
802 | </sect2> |
---|
803 | |
---|
804 | |
---|
805 | <!-- ******************* Section (Level#2) ****************** --> |
---|
806 | <sect2 id="sect.Hits.G4VPrim"> |
---|
807 | <title> |
---|
808 | Concrete classes of <emphasis>G4VPrimitiveScorer</emphasis> |
---|
809 | </title> |
---|
810 | |
---|
811 | <para> |
---|
812 | With Geant4 version 8.0, several concrete primitive scorer classes |
---|
813 | are provided, all of which are derived from the |
---|
814 | <emphasis>G4VPrimitiveScorer</emphasis> abstract base class and which are to be |
---|
815 | registered to <emphasis>G4MultiFunctionalDetector</emphasis>. Each of them |
---|
816 | contains one <emphasis>G4THitsMap</emphasis> object and scores a simple double |
---|
817 | value for each key. |
---|
818 | </para> |
---|
819 | |
---|
820 | <!-- ******* Bridgehead ******* --> |
---|
821 | <bridgehead renderas='sect4'> |
---|
822 | Track length scorers |
---|
823 | </bridgehead> |
---|
824 | |
---|
825 | <para> |
---|
826 | <variablelist><title></title> |
---|
827 | <varlistentry> |
---|
828 | <term> |
---|
829 | G4PSTrackLength |
---|
830 | </term> |
---|
831 | <listitem><para> |
---|
832 | The track length is defined as the sum of step lengths of the |
---|
833 | particles inside the cell. Bt default, the track weight is not |
---|
834 | taken into account, but could be used as a multiplier of each step |
---|
835 | length if the <emphasis>Weighted()</emphasis> method of this class object is |
---|
836 | invoked. |
---|
837 | </para></listitem> |
---|
838 | </varlistentry> |
---|
839 | <varlistentry> |
---|
840 | <term> |
---|
841 | G4PSPassageTrackLength |
---|
842 | </term> |
---|
843 | <listitem><para> |
---|
844 | The passage track length is the same as the track length in |
---|
845 | <emphasis>G4PSTrackLength</emphasis>, except that only tracks which pass |
---|
846 | through the volume are taken into account. It means newly-generated or |
---|
847 | stopped tracks inside the cell are excluded from the calculation. |
---|
848 | By default, the track weight is not taken into account, but could |
---|
849 | be used as a multiplier of each step length if the |
---|
850 | <emphasis>Weighted()</emphasis> method of this class object is invoked. |
---|
851 | </para></listitem> |
---|
852 | </varlistentry> |
---|
853 | </variablelist> |
---|
854 | </para> |
---|
855 | |
---|
856 | |
---|
857 | <!-- ******* Bridgehead ******* --> |
---|
858 | <bridgehead renderas='sect4'> |
---|
859 | <emphasis role="bold">Deposited energy scorers</emphasis> |
---|
860 | </bridgehead> |
---|
861 | |
---|
862 | <para> |
---|
863 | <variablelist><title></title> |
---|
864 | <varlistentry> |
---|
865 | <term> |
---|
866 | G4PSEnergyDeposit |
---|
867 | </term> |
---|
868 | <listitem><para> |
---|
869 | This scorer stores a sum of particles' energy deposits at each |
---|
870 | step in the cell. The particle weight is multiplied at each |
---|
871 | step. |
---|
872 | </para></listitem> |
---|
873 | </varlistentry> |
---|
874 | <varlistentry> |
---|
875 | <term> |
---|
876 | G4PSDoseDeposit |
---|
877 | </term> |
---|
878 | <listitem><para> |
---|
879 | In some cases, dose is a more convenient way to evaluate the |
---|
880 | effect of energy deposit in a cell than simple deposited energy. |
---|
881 | The dose deposit is defined by the sum of energy deposits at each |
---|
882 | step in a cell divided by the mass of the cell. The mass is |
---|
883 | calculated from the density and volume of the cell taken from the |
---|
884 | methods of <emphasis>G4VSolid</emphasis> and |
---|
885 | <emphasis>G4LogicalVolume</emphasis>. The particle |
---|
886 | weight is multiplied at each step. |
---|
887 | </para></listitem> |
---|
888 | </varlistentry> |
---|
889 | </variablelist> |
---|
890 | </para> |
---|
891 | |
---|
892 | <!-- ******* Bridgehead ******* --> |
---|
893 | <bridgehead renderas='sect4'> |
---|
894 | <emphasis role="bold">Current and flux scorers</emphasis> |
---|
895 | </bridgehead> |
---|
896 | |
---|
897 | <para> |
---|
898 | There are two different definitions of a particle's flow for a |
---|
899 | given geometry. One is a current and the other is a flux. In our |
---|
900 | scorers, the current is simply defined as the number of particles |
---|
901 | (with the particle's weight) at a certain surface or volume, while |
---|
902 | the flux takes the particle's injection angle to the geometry into |
---|
903 | account. The current and flux are usually defined at a surface, but |
---|
904 | volume current and volume flux are also provided. |
---|
905 | </para> |
---|
906 | |
---|
907 | <para> |
---|
908 | <variablelist><title></title> |
---|
909 | <varlistentry> |
---|
910 | <term> |
---|
911 | G4PSFlatSurfaceCurrent |
---|
912 | </term> |
---|
913 | <listitem><para> |
---|
914 | Flat surface current is a surface based scorer. The present |
---|
915 | implementation is limited to scoring only at the -Z surface of a |
---|
916 | <emphasis>G4Box</emphasis> solid. The quantity is defined by the number |
---|
917 | of tracks that reach the surface. The user must choose a direction of the |
---|
918 | particle to be scored. The choices are fCurrent_In, fCurrent_Out, |
---|
919 | or fCurrent_InOut, one of which must be entered as the second |
---|
920 | argument of the constructor. Here, fCurrent_In scores incoming |
---|
921 | particles to the cell, while fCurrent_Out scores only outgoing |
---|
922 | particles from the cell. fCurrent_InOut scores both directions. The |
---|
923 | current is multiplied by particle weight and is normalized for a |
---|
924 | unit area. |
---|
925 | </para></listitem> |
---|
926 | </varlistentry> |
---|
927 | <varlistentry> |
---|
928 | <term> |
---|
929 | G4PSSphereSurfaceCurrent |
---|
930 | </term> |
---|
931 | <listitem><para> |
---|
932 | Sphere surface current is a surface based scorer, and similar |
---|
933 | to the G4PSFlatSurfaceCurrent. The only difference is that the |
---|
934 | surface is defined at the <emphasis role="bold">inner surface</emphasis> |
---|
935 | of a G4Sphere solid. |
---|
936 | </para></listitem> |
---|
937 | </varlistentry> |
---|
938 | <varlistentry> |
---|
939 | <term> |
---|
940 | G4PSPassageCurrent |
---|
941 | </term> |
---|
942 | <listitem><para> |
---|
943 | Passage current is a volume-based scorer. The current is |
---|
944 | defined by the number of tracks that pass through the volume. A |
---|
945 | particle weight is applied at the exit point. A passage current is |
---|
946 | defined for a volume. |
---|
947 | </para></listitem> |
---|
948 | </varlistentry> |
---|
949 | <varlistentry> |
---|
950 | <term> |
---|
951 | G4PSFlatSurfaceFlux |
---|
952 | </term> |
---|
953 | <listitem><para> |
---|
954 | Flat surface flux is a surface based flux scorer. The surface |
---|
955 | flux is defined by the number of tracks that reach the surface. The |
---|
956 | expression of surface flux is given by the sum of W/cos(t)/A, where |
---|
957 | W, t and A represent particle weight, injection angle of particle |
---|
958 | with respect to the surface normal, and area of the surface. The |
---|
959 | user must enter one of the particle directions, fFlux_In, |
---|
960 | fFlux_Out, or fFlux_InOut in the constructor. Here, fFlux_In scores |
---|
961 | incoming particles to the cell, while fFlux_Out scores outgoing |
---|
962 | particles from the cell. fFlux_InOut scores both directions. |
---|
963 | </para></listitem> |
---|
964 | </varlistentry> |
---|
965 | <varlistentry> |
---|
966 | <term> |
---|
967 | G4PSCellFlux |
---|
968 | </term> |
---|
969 | <listitem><para> |
---|
970 | Cell flux is a volume based flux scorer. The cell flux is |
---|
971 | defined by a track length (L) of the particle inside a volume |
---|
972 | divided by the volume (V) of this cell. The track length is |
---|
973 | calculated by a sum of the step lengths in the cell. The expression |
---|
974 | for cell flux is given by the sum of (W*L)/V, where W is a particle |
---|
975 | weight, and is multiplied by the track length at each step. |
---|
976 | </para></listitem> |
---|
977 | </varlistentry> |
---|
978 | <varlistentry> |
---|
979 | <term> |
---|
980 | G4PSPassageCellFlux |
---|
981 | </term> |
---|
982 | <listitem><para> |
---|
983 | Passage cell flux is a volume based scorer similar to |
---|
984 | <emphasis>G4PSCellFlux</emphasis>. The only difference is that tracks |
---|
985 | which pass through a cell are taken into account. It means generated or |
---|
986 | stopped tracks inside the volume are excluded from the |
---|
987 | calculation. |
---|
988 | </para></listitem> |
---|
989 | </varlistentry> |
---|
990 | </variablelist> |
---|
991 | </para> |
---|
992 | |
---|
993 | <!-- ******* Bridgehead ******* --> |
---|
994 | <bridgehead renderas='sect4'> |
---|
995 | <emphasis role="bold">Other scorers</emphasis> |
---|
996 | </bridgehead> |
---|
997 | |
---|
998 | <para> |
---|
999 | <variablelist><title></title> |
---|
1000 | <varlistentry> |
---|
1001 | <term> |
---|
1002 | G4PSMinKinEAtGeneration |
---|
1003 | </term> |
---|
1004 | <listitem><para> |
---|
1005 | This scorer records the minimum kinetic energy of secondary |
---|
1006 | particles at their production point in the volume in an event. This |
---|
1007 | primitive scorer does not integrate the quantity, but records the |
---|
1008 | minimum quantity. |
---|
1009 | </para></listitem> |
---|
1010 | </varlistentry> |
---|
1011 | <varlistentry> |
---|
1012 | <term> |
---|
1013 | G4PSNofSecondary |
---|
1014 | </term> |
---|
1015 | <listitem><para> |
---|
1016 | This class scores the number of secondary particles generated |
---|
1017 | in the volume. The weight of the secondary track is taken into |
---|
1018 | account. |
---|
1019 | </para></listitem> |
---|
1020 | </varlistentry> |
---|
1021 | <varlistentry> |
---|
1022 | <term> |
---|
1023 | G4PSNofStep |
---|
1024 | </term> |
---|
1025 | <listitem><para> |
---|
1026 | This class scores the number of steps in the cell. A particle |
---|
1027 | weight is not applied. |
---|
1028 | </para></listitem> |
---|
1029 | </varlistentry> |
---|
1030 | <varlistentry> |
---|
1031 | <term> |
---|
1032 | G4PSCellCharge |
---|
1033 | </term> |
---|
1034 | <listitem><para> |
---|
1035 | This class scored the total charge of particles which has stoped |
---|
1036 | in the volume. |
---|
1037 | </para></listitem> |
---|
1038 | </varlistentry> |
---|
1039 | </variablelist> |
---|
1040 | </para> |
---|
1041 | |
---|
1042 | </sect2> |
---|
1043 | |
---|
1044 | |
---|
1045 | <!-- ******************* Section (Level#2) ****************** --> |
---|
1046 | <sect2 id="sect.Hits.G4VSDFil"> |
---|
1047 | <title> |
---|
1048 | <emphasis>G4VSDFilter</emphasis> and its derived classes |
---|
1049 | </title> |
---|
1050 | |
---|
1051 | <para> |
---|
1052 | <emphasis>G4VSDFilter</emphasis> is an abstract class that represents a track |
---|
1053 | filter to be associated with <emphasis>G4VSensitiveDetector</emphasis> or |
---|
1054 | <emphasis>G4VPrimitiveScorer</emphasis>. It defines a virtual method |
---|
1055 | |
---|
1056 | <informalexample> |
---|
1057 | <programlisting> |
---|
1058 | <emphasis>G4bool Accept(const G4Step*)</emphasis> |
---|
1059 | </programlisting> |
---|
1060 | </informalexample> |
---|
1061 | |
---|
1062 | that should return <emphasis>true</emphasis> if this particular step should be |
---|
1063 | scored by the <emphasis>G4VSensitiveDetector</emphasis> or |
---|
1064 | <emphasis>G4VPrimitiveScorer</emphasis>. |
---|
1065 | </para> |
---|
1066 | |
---|
1067 | <para> |
---|
1068 | While the user can implement his/her own filter class, Geant4 |
---|
1069 | version 8.0 provides the following concrete filter classes: |
---|
1070 | |
---|
1071 | <variablelist><title></title> |
---|
1072 | <varlistentry> |
---|
1073 | <term> |
---|
1074 | G4SDChargedFilter |
---|
1075 | </term> |
---|
1076 | <listitem><para> |
---|
1077 | All charged particles are accepted. |
---|
1078 | </para></listitem> |
---|
1079 | </varlistentry> |
---|
1080 | <varlistentry> |
---|
1081 | <term> |
---|
1082 | G4SDNeutralFilter |
---|
1083 | </term> |
---|
1084 | <listitem><para> |
---|
1085 | All neutral particles are accepted. |
---|
1086 | </para></listitem> |
---|
1087 | </varlistentry> |
---|
1088 | <varlistentry> |
---|
1089 | <term> |
---|
1090 | G4SDParticleFilter |
---|
1091 | </term> |
---|
1092 | <listitem><para> |
---|
1093 | Particle species which are registered to this filter object by |
---|
1094 | <emphasis>Add("particle_name")</emphasis> are accepted. More than one |
---|
1095 | species can be registered. |
---|
1096 | </para></listitem> |
---|
1097 | </varlistentry> |
---|
1098 | <varlistentry> |
---|
1099 | <term> |
---|
1100 | G4SDKineticEnergyFilter |
---|
1101 | </term> |
---|
1102 | <listitem><para> |
---|
1103 | A track with kinetic energy greater than or equal to EKmin and |
---|
1104 | smaller than EKmin is accepted. EKmin and EKmax should be defined |
---|
1105 | as arguments of the constructor. The default values of EKmin and |
---|
1106 | EKmax are zero and DBL_MAX. |
---|
1107 | </para></listitem> |
---|
1108 | </varlistentry> |
---|
1109 | <varlistentry> |
---|
1110 | <term> |
---|
1111 | G4SDParticleWithEnergyFilter |
---|
1112 | </term> |
---|
1113 | <listitem><para> |
---|
1114 | Combination of <emphasis>G4SDParticleFilter</emphasis> and |
---|
1115 | <emphasis>G4SDParticleWithEnergyFilter</emphasis>. |
---|
1116 | </para></listitem> |
---|
1117 | </varlistentry> |
---|
1118 | </variablelist> |
---|
1119 | </para> |
---|
1120 | |
---|
1121 | <para> |
---|
1122 | The use of the <emphasis>G4SDParticleFilter</emphasis> class is demonstrated |
---|
1123 | in <xref linkend="programlist_Hits_2" />, where filters which accept gamma, |
---|
1124 | electron, positron and electron/positron are defined. |
---|
1125 | </para> |
---|
1126 | |
---|
1127 | |
---|
1128 | </sect2> |
---|
1129 | |
---|
1130 | |
---|
1131 | <!-- ******************* Section (Level#2) ****************** --> |
---|
1132 | <sect2 id="sect.EvtBias.ScorImpRoul.Scor"> |
---|
1133 | <title> |
---|
1134 | Scoring for Event Biasing |
---|
1135 | </title> |
---|
1136 | |
---|
1137 | <para> |
---|
1138 | Scoring for Event Biasing (described in <xref linkend="sect.EvtBias" />) is a |
---|
1139 | very specific use case whereby particle weights and fluxes through importance |
---|
1140 | cells are required. The goals of the scoring technique are to: |
---|
1141 | |
---|
1142 | <itemizedlist spacing="compact"> |
---|
1143 | <listitem><para> |
---|
1144 | appraise particle quantities related to special regions or |
---|
1145 | surfaces, |
---|
1146 | </para></listitem> |
---|
1147 | <listitem><para> |
---|
1148 | be applicable to all "cells" (physical volumes or replicas) of |
---|
1149 | a given geometry, |
---|
1150 | </para></listitem> |
---|
1151 | <listitem><para> |
---|
1152 | be customizable. |
---|
1153 | </para></listitem> |
---|
1154 | </itemizedlist> |
---|
1155 | </para> |
---|
1156 | |
---|
1157 | <para> |
---|
1158 | Standard scoring must be provided for quantities such as tracks |
---|
1159 | entering a cell, average weight of entering tracks, energy of |
---|
1160 | entering tracks, and collisions inside the cell. |
---|
1161 | </para> |
---|
1162 | |
---|
1163 | <para> |
---|
1164 | A number of scorers have been created for this specific appliction: |
---|
1165 | </para> |
---|
1166 | |
---|
1167 | <para> |
---|
1168 | <variablelist><title></title> |
---|
1169 | <varlistentry> |
---|
1170 | <term> |
---|
1171 | G4PSNofCollision |
---|
1172 | </term> |
---|
1173 | <listitem><para> |
---|
1174 | This scorer records the number of collisions that occur within a scored volume/cell. |
---|
1175 | There is the additional possibility to take into account the track weight |
---|
1176 | whilst scoring the number of collisions, via the following command: |
---|
1177 | <informalexample> |
---|
1178 | <programlisting> |
---|
1179 | G4PSNofCollision* scorer1 = new G4PSNofCollision(psName="CollWeight"); |
---|
1180 | scorer1->Weighted(true); |
---|
1181 | </programlisting> |
---|
1182 | </informalexample> |
---|
1183 | </para></listitem> |
---|
1184 | </varlistentry> |
---|
1185 | <varlistentry> |
---|
1186 | <term> |
---|
1187 | G4PSPopulation |
---|
1188 | </term> |
---|
1189 | <listitem><para> |
---|
1190 | This scores the number of tracks within in a given cell per event. |
---|
1191 | </para></listitem> |
---|
1192 | </varlistentry> |
---|
1193 | <varlistentry> |
---|
1194 | <term> |
---|
1195 | G4PSTrackLength |
---|
1196 | </term> |
---|
1197 | <listitem><para> |
---|
1198 | The track lengths within a cell are measured and if, additionally, the result is desired |
---|
1199 | to be weighted then the following code has to be implemented: |
---|
1200 | <informalexample> |
---|
1201 | <programlisting> |
---|
1202 | G4PSTrackLength* scorer5 = new G4PSTrackLength(psName="SLW"); |
---|
1203 | scorer5->Weighted(true); |
---|
1204 | </programlisting> |
---|
1205 | </informalexample> |
---|
1206 | Further if the energy track flux is required then the following should be |
---|
1207 | implemented: |
---|
1208 | <informalexample> |
---|
1209 | <programlisting> |
---|
1210 | G4PSTrackLength* scorer6 = new G4PSTrackLength(psName="SLWE"); |
---|
1211 | scorer6->Weighted(true); |
---|
1212 | scorer6->MultiplyKineticEnergy(true); |
---|
1213 | MFDet->RegisterPrimitive(scorer6); |
---|
1214 | </programlisting> |
---|
1215 | </informalexample> |
---|
1216 | |
---|
1217 | Alternatively to measure the flux per unit velocity then: |
---|
1218 | <informalexample> |
---|
1219 | <programlisting> |
---|
1220 | G4PSTrackLength* scorer7 = new G4PSTrackLength(psName="SLW_V"); |
---|
1221 | scorer7->Weighted(true); |
---|
1222 | scorer7->DivideByVelocity(true); |
---|
1223 | MFDet->RegisterPrimitive(scorer7); |
---|
1224 | </programlisting> |
---|
1225 | </informalexample> |
---|
1226 | |
---|
1227 | Finally to measure the flux energy per unit velocity then: |
---|
1228 | <informalexample> |
---|
1229 | <programlisting> |
---|
1230 | G4PSTrackLength* scorer8 = new G4PSTrackLength(psName="SLWE_V"); |
---|
1231 | scorer8->Weighted(true); |
---|
1232 | scorer8->MultiplyKineticEnergy(true); |
---|
1233 | scorer8->DivideByVelocity(true); |
---|
1234 | MFDet->RegisterPrimitive(scorer8); |
---|
1235 | </programlisting> |
---|
1236 | </informalexample> |
---|
1237 | </para></listitem> |
---|
1238 | </varlistentry> |
---|
1239 | </variablelist> |
---|
1240 | </para> |
---|
1241 | |
---|
1242 | |
---|
1243 | </sect2> |
---|
1244 | |
---|
1245 | </sect1> |
---|