include/root/TGenPhaseSpace.h

0001 // @(#)root/physics:$Id$
0002 // Author: Rene Brun , Valerio Filippini  06/09/2000
0003
0004 ///////////////////////////////////////////////////////////////////////////////
0005 //                                                                           //
0006 //   Phase Space Generator, based on the GENBOD routine of CERNLIB           //
0007 //                                                                           //
0008 ///////////////////////////////////////////////////////////////////////////////
0009
0010 #ifndef ROOT_TGenPhaseSpace
0011 #define ROOT_TGenPhaseSpace
0012
0013 #include "TLorentzVector.h"
0014
0015 class TGenPhaseSpace : public TObject {
0016 private:
0017    Int_t        fNt;             // number of decay particles
0018    Double_t     fMass[18];       // masses of particles
0019    Double_t     fBeta[3];        // betas of decaying particle
0020    Double_t     fTeCmTm;         // total energy in the C.M. minus the total mass
0021    Double_t     fWtMax;          // maximum weight
0022    TLorentzVector  fDecPro[18];  //kinematics of the generated particles
0023
0024    Double_t PDK(Double_t a, Double_t b, Double_t c);
0025
0026 public:
0027    TGenPhaseSpace(): fNt(0), fMass(), fBeta(), fTeCmTm(0.), fWtMax(0.) {}
0028    TGenPhaseSpace(const TGenPhaseSpace &gen);
0029    ~TGenPhaseSpace() override {}
0030    TGenPhaseSpace& operator=(const TGenPhaseSpace &gen);
0031
0032    Bool_t          SetDecay(TLorentzVector &P, Int_t nt, const Double_t *mass, Option_t *opt="");
0033    Double_t        Generate();
0034    TLorentzVector *GetDecay(Int_t n);
0035
0036    Int_t    GetNt()      const { return fNt;}
0037    Double_t GetWtMax()   const { return fWtMax;}
0038
0039    ClassDefOverride(TGenPhaseSpace,1) //Simple Phase Space Generator
0040 };
0041
0042 #endif
0043