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00029 #include "globals.hh"
00030 #include "G4SystemOfUnits.hh"
00031 #include "G4CollisionComposite.hh"
00032 #include "G4VCollision.hh"
00033 #include "G4CollisionVector.hh"
00034 #include "G4KineticTrack.hh"
00035 #include "G4KineticTrackVector.hh"
00036 #include "G4VCrossSectionSource.hh"
00037 #include "G4HadTmpUtil.hh"
00038
00039 const G4int G4CollisionComposite::nPoints = 32;
00040
00041 G4double G4CollisionComposite::theT[nPoints] =
00042 {.01, .03, .05, .1, .15, .2, .3, .4, .5, .6, .7, .8, .9, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0, 8.0, 10., 15, 20, 50, 100};
00043
00044 G4CollisionComposite::G4CollisionComposite()
00045 {
00046 }
00047
00048
00049 G4CollisionComposite::~G4CollisionComposite()
00050 {
00051 std::for_each(components.begin(), components.end(), G4Delete());
00052 }
00053
00054
00055 G4double G4CollisionComposite::CrossSection(const G4KineticTrack& trk1,
00056 const G4KineticTrack& trk2) const
00057 {
00058 G4double crossSect = 0.;
00059 const G4VCrossSectionSource* xSource = GetCrossSectionSource();
00060 if (xSource != 0)
00061
00062 {
00063 crossSect = xSource->CrossSection(trk1,trk2);
00064 }
00065 else
00066 {
00067
00068 const_cast<G4CollisionComposite *>(this)->BufferCrossSection(trk1.GetDefinition(), trk2.GetDefinition());
00069
00070 crossSect = BufferedCrossSection(trk1,trk2);
00071 }
00072 return crossSect;
00073 }
00074
00075
00076 G4KineticTrackVector* G4CollisionComposite::FinalState(const G4KineticTrack& trk1,
00077 const G4KineticTrack& trk2) const
00078 {
00079 std::vector<G4double> cxCache;
00080 G4double partialCxSum = 0.0;
00081
00082 size_t i;
00083 for (i=0; i<components.size(); i++)
00084 {
00085 G4double partialCx;
00086
00087 if (components[i]->IsInCharge(trk1,trk2))
00088 {
00089 partialCx = components[i]->CrossSection(trk1,trk2);
00090 }
00091 else
00092 {
00093 partialCx = 0.0;
00094 }
00095
00096 partialCxSum += partialCx;
00097 cxCache.push_back(partialCx);
00098 }
00099
00100 G4double random = G4UniformRand()*partialCxSum;
00101 G4double running = 0;
00102 for (i=0; i<cxCache.size(); i++)
00103 {
00104 running += cxCache[i];
00105 if (running > random)
00106 {
00107 return components[i]->FinalState(trk1, trk2);
00108 }
00109 }
00110
00111
00112
00113
00114 return NULL;
00115 }
00116
00117
00118 G4bool G4CollisionComposite::IsInCharge(const G4KineticTrack& trk1,
00119 const G4KineticTrack& trk2) const
00120 {
00121 G4bool isInCharge = false;
00122
00123
00124
00125 const G4CollisionVector* comps = GetComponents();
00126 if (comps)
00127 {
00128 G4CollisionVector::const_iterator iter;
00129 for (iter = comps->begin(); iter != comps->end(); ++iter)
00130 {
00131 if ( ((*iter))->IsInCharge(trk1,trk2) ) isInCharge = true;
00132 }
00133 }
00134
00135 return isInCharge;
00136 }
00137
00138 void G4CollisionComposite::
00139 BufferCrossSection(const G4ParticleDefinition * aP, const G4ParticleDefinition * bP)
00140 {
00141
00142 size_t i;
00143 for(i=0; i<theBuffer.size(); i++)
00144 {
00145 if(theBuffer[i].InCharge(aP, bP)) return;
00146 }
00147
00148
00149
00150 G4CrossSectionBuffer aNewBuff(aP, bP);
00151 size_t maxE=nPoints;
00152 for(size_t tt=0; tt<maxE; tt++)
00153 {
00154 G4double aT = theT[tt]*GeV;
00155 G4double crossSect = 0;
00156
00157
00158
00159
00160
00161 G4double atime = 0;
00162 G4double btime = 0;
00163 G4ThreeVector aPosition(0,0,0);
00164 G4ThreeVector bPosition(0,0,0);
00165 G4double aM = aP->GetPDGMass();
00166 G4double bM = bP->GetPDGMass();
00167 G4double aE = aM;
00168 G4double bE = bM;
00169 G4ThreeVector aMom(0,0,0);
00170 G4ThreeVector bMom(0,0,0);
00171 if ( aM <= bM ) {
00172 aE += aT;
00173 aMom = G4ThreeVector(0,0,std::sqrt(aE*aE-aM*aM));
00174 } else {
00175 bE += aT;
00176 bMom = G4ThreeVector(0,0,std::sqrt(bE*bE-bM*bM));
00177 }
00178 G4LorentzVector a4Momentum(aE, aMom);
00179 G4LorentzVector b4Momentum(bE, bMom);
00180 G4KineticTrack a(const_cast<G4ParticleDefinition *>(aP), atime, aPosition, a4Momentum);
00181 G4KineticTrack b(const_cast<G4ParticleDefinition *>(bP), btime, bPosition, b4Momentum);
00182
00183 for (i=0; i<components.size(); i++)
00184 {
00185 if(components[i]->IsInCharge(a,b))
00186 {
00187 crossSect += components[i]->CrossSection(a,b);
00188 }
00189 }
00190 G4double sqrts = (a4Momentum+b4Momentum).mag();
00191 aNewBuff.push_back(sqrts, crossSect);
00192 }
00193 theBuffer.push_back(aNewBuff);
00194
00195 }
00196
00197
00198 G4double G4CollisionComposite::
00199 BufferedCrossSection(const G4KineticTrack& trk1, const G4KineticTrack& trk2) const
00200 {
00201 for(size_t i=0; i<theBuffer.size(); i++)
00202 {
00203 if(theBuffer[i].InCharge(trk1.GetDefinition(), trk2.GetDefinition()))
00204 {
00205 return theBuffer[i].CrossSection(trk1, trk2);
00206 }
00207 }
00208 throw G4HadronicException(__FILE__, __LINE__, "G4CollisionComposite::BufferedCrossSection - Blitz !!");
00209 return 0;
00210 }
00211