Gabriele Cosmo
137 lines
4.6 KiB
C++
137 lines
4.6 KiB
C++
//
|
|
// ********************************************************************
|
|
// * License and Disclaimer *
|
|
// * *
|
|
// * The Geant4 software is copyright of the Copyright Holders of *
|
|
// * the Geant4 Collaboration. It is provided under the terms and *
|
|
// * conditions of the Geant4 Software License, included in the file *
|
|
// * LICENSE and available at http://cern.ch/geant4/license . These *
|
|
// * include a list of copyright holders. *
|
|
// * *
|
|
// * Neither the authors of this software system, nor their employing *
|
|
// * institutes,nor the agencies providing financial support for this *
|
|
// * work make any representation or warranty, express or implied, *
|
|
// * regarding this software system or assume any liability for its *
|
|
// * use. Please see the license in the file LICENSE and URL above *
|
|
// * for the full disclaimer and the limitation of liability. *
|
|
// * *
|
|
// * This code implementation is the result of the scientific and *
|
|
// * technical work of the GEANT4 collaboration. *
|
|
// * By using, copying, modifying or distributing the software (or *
|
|
// * any work based on the software) you agree to acknowledge its *
|
|
// * use in resulting scientific publications, and indicate your *
|
|
// * acceptance of all terms of the Geant4 Software license. *
|
|
// ********************************************************************
|
|
//
|
|
//
|
|
// -------------------------------------------------------------------
|
|
// GEANT4 Class file
|
|
//
|
|
// For information related to this code contact:
|
|
//
|
|
// File name: G4XAqmTotal
|
|
//
|
|
// Author:
|
|
//
|
|
// Creation date: 15 April 1999
|
|
//
|
|
// Modifications:
|
|
//
|
|
// Additive Quark Model total cross section
|
|
// (H.J. Lipkin and F. Scheck, Phys.Rev. 16 (1966) 71
|
|
//
|
|
// -------------------------------------------------------------------
|
|
|
|
#include "globals.hh"
|
|
#include "G4ios.hh"
|
|
#include "G4XAqmTotal.hh"
|
|
#include "G4KineticTrack.hh"
|
|
#include "G4ParticleDefinition.hh"
|
|
|
|
|
|
// Validity range of this cross-section
|
|
const G4double G4XAqmTotal::_lowLimit = 0.;
|
|
const G4double G4XAqmTotal::_highLimit = DBL_MAX;
|
|
|
|
G4XAqmTotal::G4XAqmTotal()
|
|
{
|
|
// As a first approximation the model is assumed to be valid over
|
|
// the entire energy range
|
|
}
|
|
|
|
|
|
G4XAqmTotal::~G4XAqmTotal()
|
|
{ }
|
|
|
|
|
|
G4bool G4XAqmTotal::operator==(const G4XAqmTotal &right) const
|
|
{
|
|
return (this == (G4XAqmTotal *) &right);
|
|
}
|
|
|
|
|
|
G4bool G4XAqmTotal::operator!=(const G4XAqmTotal &right) const
|
|
{
|
|
return (this != (G4XAqmTotal *) &right);
|
|
}
|
|
|
|
|
|
G4double G4XAqmTotal::CrossSection(const G4KineticTrack& trk1, const G4KineticTrack& trk2) const
|
|
{
|
|
G4double sigma = 0.;
|
|
|
|
// Get strangeness content
|
|
G4ParticleDefinition* def1 = trk1.GetDefinition();
|
|
G4int sTrk1 = def1->GetQuarkContent(3) + def1->GetAntiQuarkContent(3);
|
|
G4ParticleDefinition* def2 = trk2.GetDefinition();
|
|
G4int sTrk2 = def2->GetQuarkContent(3) + def2->GetAntiQuarkContent(3);
|
|
|
|
// Get non-strange quark content
|
|
G4int qTrk1 = def1->GetQuarkContent(1) + def1->GetAntiQuarkContent(1) +
|
|
def1->GetQuarkContent(2) + def1->GetAntiQuarkContent(2) +
|
|
def1->GetQuarkContent(4) + def1->GetAntiQuarkContent(4) +
|
|
def1->GetQuarkContent(5) + def1->GetAntiQuarkContent(5) +
|
|
def1->GetQuarkContent(6) + def1->GetAntiQuarkContent(6);
|
|
|
|
G4int qTrk2 = def2->GetQuarkContent(1) + def2->GetAntiQuarkContent(1) +
|
|
def2->GetQuarkContent(2) + def2->GetAntiQuarkContent(2) +
|
|
def2->GetQuarkContent(4) + def2->GetAntiQuarkContent(4) +
|
|
def2->GetQuarkContent(5) + def2->GetAntiQuarkContent(5) +
|
|
def2->GetQuarkContent(6) + def2->GetAntiQuarkContent(6);
|
|
|
|
G4double sRatio1 = 0.;
|
|
if (qTrk1 != 0) sRatio1 = sTrk1 / qTrk1;
|
|
|
|
G4double sRatio2 = 0.;
|
|
if (qTrk2 != 0) sRatio2 = sTrk2 / qTrk2;
|
|
|
|
// Calculate the number of colliding mesons
|
|
G4int nMesons = 0;
|
|
G4int nQ1 = sTrk1 + qTrk1;
|
|
|
|
if (nQ1 == 2) nMesons++;
|
|
G4int nQ2 = sTrk2 + qTrk2;
|
|
if (nQ2 == 2) nMesons++;
|
|
|
|
// Cross-section (units to be checked!)
|
|
sigma = 40. * std::pow((2.0/3.0),nMesons) * (1. - 0.4 * sRatio1) * (1. - 0.4 * sRatio2) * millibarn;
|
|
|
|
return sigma;
|
|
}
|
|
|
|
|
|
G4String G4XAqmTotal::Name() const
|
|
{
|
|
G4String name("AqmTotalCrossSection");
|
|
return name;
|
|
}
|
|
|
|
|
|
|
|
G4bool G4XAqmTotal::IsValid(G4double e) const
|
|
{
|
|
G4bool answer = InLimits(e,_lowLimit,_highLimit);
|
|
|
|
return answer;
|
|
}
|