include/EvtGenModels/EvtWnPi.hh

0001
0002 /***********************************************************************
0003 * Copyright 1998-2020 CERN for the benefit of the EvtGen authors       *
0004 *                                                                      *
0005 * This file is part of EvtGen.                                         *
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0020
0021 #ifndef EvtWNPI_HH
0022 #define EvtWNPI_HH
0023
0024 #include "EvtGenBase/EvtPatches.hh"
0025 #include "EvtGenBase/EvtTensor4C.hh"
0026 #include "EvtGenBase/EvtVector4C.hh"
0027 #include "EvtGenBase/EvtVector4R.hh"
0028
0029 // Description: Routine to calculate W -> (n pi) current
0030 //          according to [Kuhn, Was, Acta.Phys.Polon B39 (2008) 147]
0031
0032 class EvtWnPi {
0033   public:
0034     EvtVector4C WCurrent( EvtVector4R q1 );
0035     EvtVector4C WCurrent( EvtVector4R q1, EvtVector4R q2 );
0036     EvtVector4C WCurrent( EvtVector4R q1, EvtVector4R q2, EvtVector4R q3 );
0037     EvtVector4C WCurrent( EvtVector4R q1, EvtVector4R q2, EvtVector4R q3,
0038                           EvtVector4R q4, EvtVector4R q5 );
0039
0040   protected:
0041     EvtVector4C JB( EvtVector4R q1, EvtVector4R q2, EvtVector4R q3,
0042                     EvtVector4R q4, EvtVector4R q5 );
0043     EvtComplex BWa( EvtVector4R q );
0044     EvtComplex BWf( EvtVector4R q );
0045     EvtComplex BWr( EvtVector4R q );
0046     double pi3G( double Q2 );
0047 };
0048
0049 #endif