include/EvtGenModels/EvtPsi2JpsiPiPi.hh

0001
0002 /***********************************************************************
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0020
0021 #ifndef EVTPSI2JPSIPIPI_HH
0022 #define EVTPSI2JPSIPIPI_HH
0023
0024 #include "EvtGenBase/EvtDecayAmp.hh"
0025
0026 #include <array>
0027 #include <string>
0028
0029 class EvtDecayBase;
0030 class EvtParticle;
0031
0032 // Description: Header file for the model "PSI2JPSIPIPI" which generates
0033 //              psi2S -> J/psi pi+ pi- decays based on hep-ph/1507.07985
0034
0035 class EvtPsi2JpsiPiPi : public EvtDecayAmp {
0036   public:
0037     EvtPsi2JpsiPiPi();
0038
0039     std::string getName() override;
0040     EvtDecayBase* clone() override;
0041     void initProbMax() override;
0042     void init() override;
0043     void decay( EvtParticle* p ) override;
0044
0045   private:
0046     bool tree;
0047     double phi;    // LO vs NLO mixing angle (radians)
0048     double cosPhi, cos2Phi, sinPhi, sin2Phi;
0049     // NLO corrections
0050     static const int nQ = 6;    // number of terms in mPiPi interpolation
0051     std::array<double, nQ> c0, c1, c2, s1, s2;
0052
0053     void setNLOArrays();
0054 };
0055
0056 #endif