00001 // 00002 // ******************************************************************** 00003 // * License and Disclaimer * 00004 // * * 00005 // * The Geant4 software is copyright of the Copyright Holders of * 00006 // * the Geant4 Collaboration. It is provided under the terms and * 00007 // * conditions of the Geant4 Software License, included in the file * 00008 // * LICENSE and available at http://cern.ch/geant4/license . These * 00009 // * include a list of copyright holders. * 00010 // * * 00011 // * Neither the authors of this software system, nor their employing * 00012 // * institutes,nor the agencies providing financial support for this * 00013 // * work make any representation or warranty, express or implied, * 00014 // * regarding this software system or assume any liability for its * 00015 // * use. Please see the license in the file LICENSE and URL above * 00016 // * for the full disclaimer and the limitation of liability. * 00017 // * * 00018 // * This code implementation is the result of the scientific and * 00019 // * technical work of the GEANT4 collaboration. * 00020 // * By using, copying, modifying or distributing the software (or * 00021 // * any work based on the software) you agree to acknowledge its * 00022 // * use in resulting scientific publications, and indicate your * 00023 // * acceptance of all terms of the Geant4 Software license. * 00024 // ******************************************************************** 00025 // 00026 // 00027 // $Id$ 00028 // Maxim Komogorov 00029 // 00030 // ----------------------------------------------------------------------------- 00031 // GEANT 4 class implementation file 00032 // 00033 // History: first implementation, Maxim Komogorov, 10-Oct-1998 00034 // ----------------------------------------------------------------------------- 00035 00036 #include "G4VKinkyStringDecay.hh" 00037 #include "G4KineticTrackVector.hh" 00038 #include "G4KineticTrack.hh" 00039 #include "Randomize.hh" 00040 00041 //***************************************************************************************************** 00042 00043 G4VKinkyStringDecay::G4VKinkyStringDecay(G4VLongitudinalStringDecay* theModal) 00044 { 00045 this->SetLongitudinalStringDecay(theModal); 00046 } 00047 00048 //***************************************************************************************************** 00049 00050 G4double G4VKinkyStringDecay::GetLightConeGluonZ(G4double zmin, G4double zmax) 00051 { 00052 G4double z, yf; 00053 do { 00054 z = zmin + G4UniformRand()*(zmax-zmin); 00055 yf = z*z +sqr(1 - z); 00056 } 00057 while (G4UniformRand() > yf); 00058 return z; 00059 } 00060 00061 //***************************************************************************************************** 00062 00063 G4KineticTrackVector* G4VKinkyStringDecay::FragmentString(const G4ExcitedString& String) 00064 { 00065 G4LorentzVector Mom = String.GetGluon()->Get4Momentum(); 00066 G4ThreeVector Pos = String.GetGluon()->GetPosition(); 00067 G4int QuarkEncoding = theLongitudinalStringDecay->SampleQuarkFlavor(); 00068 G4ThreeVector Pquark=theLongitudinalStringDecay->SampleQuarkPt(); 00069 G4double Pt2 = Pquark.mag2(); 00070 G4double z = GetLightConeGluonZ(0, 1); 00071 G4double w = Mom.e() + Mom.pz(); 00072 //... now compute quark longitudinal momentum and energy 00073 00074 Pquark.setZ( (z*w - Pt2/(z*w))*0.5); 00075 G4double E = (z*w + Pt2/(z*w))*0.5; 00076 00077 G4Parton* AntiColor = new G4Parton(-QuarkEncoding); 00078 AntiColor->SetPosition(Pos); 00079 G4LorentzVector AntiColorMom(-Pquark, E); 00080 AntiColor->Set4Momentum(AntiColorMom); 00081 G4Parton* Color = new G4Parton(*String.GetColorParton()); 00082 G4ExcitedString Str1(Color, AntiColor, String.GetDirection()); 00083 G4KineticTrackVector* KTV1 = theLongitudinalStringDecay->FragmentString(Str1); 00084 00085 Color = new G4Parton(QuarkEncoding); 00086 Color->SetPosition(Pos); 00087 G4LorentzVector ColorMom(Pquark, E); 00088 Color->Set4Momentum(ColorMom); 00089 AntiColor = new G4Parton(*String.GetAntiColorParton()); 00090 G4ExcitedString Str2(Color, AntiColor, String.GetDirection()); 00091 G4KineticTrackVector* KTV2 = theLongitudinalStringDecay->FragmentString(Str2); 00092 00093 if (KTV1 && KTV2) 00094 while(!KTV2->empty()) 00095 { 00096 KTV1->push_back(KTV2->back()); 00097 KTV1->erase(KTV1->end()-1); 00098 } 00099 return KTV1; 00100 } 00101 00102 //***************************************************************************************************** 00103 00104 00105 00106 00107 00108 00109 00110 00111 00112 00113 00114 00115 00116