include/EvtGenModels/EvtVectorIsr.hh

0001
0002 /***********************************************************************
0003 * Copyright 1998-2020 CERN for the benefit of the EvtGen authors       *
0004 *                                                                      *
0005 * This file is part of EvtGen.                                         *
0006 *                                                                      *
0007 * EvtGen is free software: you can redistribute it and/or modify       *
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0010 * (at your option) any later version.                                  *
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0014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
0015 * GNU General Public License for more details.                         *
0016 *                                                                      *
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0019 ***********************************************************************/
0020
0021 #ifndef EVTVECTORISR_HH
0022 #define EVTVECTORISR_HH
0023
0024 #include "EvtGenBase/EvtDecayIncoherent.hh"
0025
0026 class EvtParticle;
0027
0028 // Description:
0029 //   This is a special decay model to generate e+e- -> phi gamma + soft gammas
0030 //   using soft collinear ISR calculation from AfkQed
0031 //   This is implemented as a decay of the VPHO.
0032
0033 class EvtVectorIsr : public EvtDecayIncoherent {
0034   public:
0035     std::string getName() override;
0036
0037     EvtDecayBase* clone() override;
0038
0039     void decay( EvtParticle* p ) override;
0040
0041     void init() override;
0042
0043     void initProbMax() override;
0044
0045     double ckhrad1( double xx, double a, double b );
0046
0047     void ckhrad( const double& e_beam, const double& q2_min, double& e01,
0048                  double& e02, double& f );
0049
0050   private:
0051     double csfrmn, csbkmn;
0052     double fmax;
0053     bool firstorder;
0054 };
0055
0056 #endif