1 ///////////////////////////////////////////////////////////////////////////
5 // This file is part of starlight.
7 // starlight is free software: you can redistribute it and/or modify
8 // it under the terms of the GNU General Public License as published by
9 // the Free Software Foundation, either version 3 of the License, or
10 // (at your option) any later version.
12 // starlight is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with starlight. If not, see <http://www.gnu.org/licenses/>.
20 ///////////////////////////////////////////////////////////////////////////
22 // File and Version Information:
23 // $Rev:: 192 $: revision of last commit
24 // $Author:: jnystrand $: author of last commit
25 // $Date:: 2014-12-01 20:39:25 +0100 #$: date of last commit
31 ///////////////////////////////////////////////////////////////////////////
34 #ifndef PHOTONNUCLEUSCROSSSECTION_H
35 #define PHOTONNUCLEUSCROSSSECTION_H
38 #include "starlightconstants.h"
39 #include "beambeamsystem.h"
42 class photonNucleusCrossSection {
46 photonNucleusCrossSection(const beamBeamSystem& bbsystem);
47 ~photonNucleusCrossSection();
49 double slopeParameter () const { return _slopeParameter; } ///< returns slope of t-distribution [(GeV/c)^{-2}]
50 double getChannelMass () const { return _channelMass; } ///< returns mass of the produced system [GeV/c^2]
51 double getBNORM () const { return _BNORM; }
52 double luminosity () const { return _luminosity; } ///< returns luminosity [10^{26} cm^{-2} sec^{-1}]
53 beamBeamSystem getbbs () const { return _bbs; } ///< returns beamBeamSystem
54 double vmPhotonCoupling() const { return _vmPhotonCoupling; } ///< vectormeson-photon coupling constant f_v / 4 pi (cf. Eq. 10 in KN PRC 60 (1999) 014903)
55 double getDefaultC () const { return _defaultC; }
56 double maxPhotonEnergy () const { return _maxPhotonEnergy; } ///< returns max photon energy in lab frame [GeV] (for vectormesons only)
58 void crossSectionCalculation(const double bwnormsave);
59 // Will think about it...For VMs we just calculate it
60 // So just use the wide or narrow constructor to calculate it
61 // wide/narrow will inherit this.
62 double getcsgA(const double Egamma,
65 double photonFlux(const double Egamma,
67 double sigmagp(const double Wgp);
68 double sigma_A(const double sig_N,
70 double sigma_N(const double Wgp);
71 double breitWigner(const double W,
73 double nepoint(const double Egamma,
77 const unsigned int _nWbins;
78 const unsigned int _nYbins;
84 const double _beamLorentzGamma;
90 // copied from inputParameters
92 starlightConstants::particleTypeEnum _particleType;
93 int _beamBreakupMode; ///< breakup mode for beam particles
94 bool _coherentProduction; ///< if true, production is coherent, else incoherent
95 double _incoherentFactor; ///< allows to scale the incoherent contribution in vector meson production
99 // locally defined parameters
100 double _slopeParameter; ///< slope of t-distribution [(GeV/c)^{-2}]
101 double _vmPhotonCoupling; ///< vectormeson-photon coupling constant f_v / 4 pi (cf. Eq. 10 in KN PRC 60 (1999) 014903)
105 double _luminosity; ///< luminosity [10^{26} cm^{-2} sec^{-1}]
106 double _maxPhotonEnergy; ///< max photon energy in lab frame [GeV] (for vectormesons only)
107 double _width; ///< width of the produced system [GeV/c^2]
108 double _channelMass; ///< mass of the produced system [GeV/c^2]
113 #endif // PHOTONNUCLEUSCROSSSECTION_H