/******************************************************************************************************** * Author: Dominik Flierl, flierl@ikf.uni-frankfurt.de ******************************************************************************************************** * This class returns the coulomb weight for a pair with a given momentum difference qinv * Analytical formula are based on Phys. Lett. B 432(1998)248-257 and Nucl. Phys. A610 (1996) 286c-296c ********************************************************************************************************/ #ifndef T49HbtCoulomb_hh #define T49HbtCoulomb_hh #include "TObject.h" class T49HbtCoulomb: public TObject { public : // Constructor & destructor T49HbtCoulomb() ; ~T49HbtCoulomb() ; // Like sign specific member functions // return the coulomb weight factor according to equation 8 // in Sinyukov et al., Phys. Lett. B 432(1998)248-257 for like sign pairs Double_t Weight(Double_t qinv) ; Double_t Ac(Double_t qinv) ; // gamov function void CalculateConstants() ; // init constants Double_t GetConstant1() { return fConstant1 ; } ; Double_t GetCriticalMomentum() { return fCriticalMomentum ; } ; // UNlike sign specific member functions // return the coulomb weight factor according to equation 8 Double_t WeightUnlikeSignPairs(Double_t qinv) ; Double_t AcUSP(Double_t qinv) ; // gamov function void CalculateConstantsUSP() ; // init constants Double_t GetConstant1USP() { return fConstant1USP ; } ; Double_t GetCriticalMomentumUSP() { return fCriticalMomentumUSP ; } ; // Some general setters & getters Double_t GetMeanSeparation() { return fMeanSeparation ; } ; void SetMeanSeparation(Double_t MeanSeparation) ; // The coulomb correction derived in a simple toy model given in // G. Baym & PBM, Nucl. Phys. A610 (1996) 286c-296c Double_t ClassicalWeight(Double_t qinv) ; Double_t ClassicalWeightUnlikeSignPairs(Double_t qinv) ; private : // Constants Double_t f_hbc ; // hbc = 0.2 [Gev][fm] adjust natural units: hb=c=1 Double_t fMeanSeparation ; // in the paper =~ radius of the source Double_t f_d2 ; // d2 in the paper = constant = 3pi/8 // Like sign specific constants Double_t fBohrRadius ; // a in the paper = bohr Radius = 388 fm for like sign pion-pion system Double_t fConstant1 ; // equation 9 in the paper Double_t fConstant2 ; // equation 10 in the paper Double_t fCriticalMomentum ; // crossover momentum k~ in the paper equation 9 Double_t fCriticalMomentum2 ; // square of the crossovermomentum // Unlike sign specific constants Double_t fBohrRadiusUSP ; // a in the paper = bohr Radius = -388 fm for UNlike sign pion-pion system Double_t fConstant1USP ; // equation 9 in the paper Double_t fConstant2USP ; // equation 10 in the paper Double_t fCriticalMomentumUSP ; // crossover momentum k~ in the paper equation 9 Double_t fCriticalMomentumUSP2 ; // square of the crossovermomentum ClassDef(T49HbtCoulomb,1) ; } ; #endif