Gabriele Cosmo
96 lines
3.4 KiB
C++
96 lines
3.4 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. *
|
|
// ********************************************************************
|
|
//
|
|
//
|
|
//
|
|
// Hadronic Process: Nuclear De-excitations
|
|
// by V. Lara (Oct 1998)
|
|
//
|
|
//J. M. Quesada (May 2009): sigma_sym (SigmaS) tuned for spallation data.
|
|
//J. M. Quesada (30.10.09): retuning for IAEA spallation data
|
|
|
|
#include "G4FissionParameters.hh"
|
|
#include "G4SystemOfUnits.hh"
|
|
|
|
G4FissionParameters::G4FissionParameters()
|
|
: A1(134),A2(141),A3((A1 + A2)*0.5),As(0.0),Sigma1(0.0),Sigma2(0.0),
|
|
SigmaS(0.),w(0.0)
|
|
{}
|
|
|
|
G4FissionParameters::~G4FissionParameters()
|
|
{}
|
|
|
|
void G4FissionParameters::DefineParameters(G4int A, G4int Z, G4double ExEnergy,
|
|
G4double FissionBarrier)
|
|
{
|
|
// to avoid usage of units
|
|
G4double U = std::min(200., ExEnergy/CLHEP::MeV);
|
|
|
|
As = A*0.5;
|
|
|
|
if (A <= 235) { Sigma2 = 5.6; }
|
|
else { Sigma2 = 5.6 + 0.096*(A-235); }
|
|
|
|
Sigma1 = 0.5*Sigma2;
|
|
|
|
//JMQ 310509
|
|
// if (SigmaS > 20.0) SigmaS = 20.0;
|
|
// SigmaS*=1.3;
|
|
//JMQ 301009: retuning (after CEM transition prob.have been chosen as default)
|
|
SigmaS = 0.8*G4Exp(0.00553*U + 2.1386);
|
|
|
|
G4double wa = 0.0;
|
|
w = 0.0;
|
|
if (Z >= 90) {
|
|
if (U <= 16.25) { wa = G4Exp(0.5385*U-9.9564); }
|
|
else { wa = G4Exp(0.09197*U-2.7003); }
|
|
} else if (Z == 89) {
|
|
wa = G4Exp(0.09197*U-1.0808);
|
|
} else if (Z >= 82) {
|
|
G4double X = std::max(0.0, FissionBarrier/CLHEP::MeV - 7.5);
|
|
wa = G4Exp(0.09197*(U-X) - 1.0808);
|
|
} else { // Z < 82
|
|
w = 1001.0;
|
|
}
|
|
|
|
if (Z >= 82) {
|
|
G4double x1 = (A1-As)/Sigma1;
|
|
G4double x2 = (A2-As)/Sigma2;
|
|
G4double FasymAsym = 2*LocalExp(x2) + LocalExp(x1);
|
|
|
|
G4double x3 = (As-A3)/SigmaS;
|
|
G4double FsymA1A2 = LocalExp(x3);
|
|
|
|
G4double w1 = std::max(1.03*wa - FasymAsym, 0.0001);
|
|
G4double w2 = std::max(1.0 - FsymA1A2*wa, 0.0001);
|
|
|
|
w = w1/w2;
|
|
|
|
if (A < 227) { w *= G4Exp(0.3*(227-A)); }
|
|
}
|
|
}
|
|
|
|
|