include/EvtGenModels/EvtVub.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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0014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        *
0015 * GNU General Public License for more details.                         *
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0019 ***********************************************************************/
0020
0021 #ifndef EVTVUB_HH
0022 #define EVTVUB_HH
0023
0024 #include "EvtGenBase/EvtDecayIncoherent.hh"
0025
0026 #include "EvtGenModels/EvtVubdGamma.hh"
0027
0028 #include <memory>
0029 #include <vector>
0030
0031 class EvtParticle;
0032
0033 // Description:
0034 // Class to generate inclusive B to X_u l nu decays according to various
0035 // decay models. Implemtented are ACCM, parton-model and a QCD model.
0036
0037 class EvtVub : public EvtDecayIncoherent {
0038   public:
0039     std::string getName() override;
0040
0041     EvtDecayBase* clone() override;
0042
0043     void initProbMax() override;
0044
0045     void init() override;
0046
0047     void decay( EvtParticle* p ) override;
0048
0049   private:
0050     double _mb;        // the b-quark pole mass in GeV (try 4.65 to 4.9)
0051     double _a;         // Parameter for the Fermi Motion (1.29 is good)
0052     double _alphas;    // Strong Coupling at m_b (around 0.24)
0053     double _dGMax;     // max dGamma*p2 value;
0054     int _nbins;
0055     int _storeQplus;
0056     std::vector<double> _masses;
0057     std::vector<double> _weights;
0058
0059     std::unique_ptr<EvtVubdGamma> _dGamma;    // calculates the decay rate
0060     double findPFermi();
0061     std::vector<double> _pf;
0062 };
0063
0064 #endif