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G4VPolarizedCrossSection.cc
Go to the documentation of this file.
Or view
the newest version in sPHENIX GitHub for file G4VPolarizedCrossSection.cc
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//
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// ********************************************************************
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// * License and Disclaimer *
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// * *
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// * The Geant4 software is copyright of the Copyright Holders of *
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// * the Geant4 Collaboration. It is provided under the terms and *
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// * conditions of the Geant4 Software License, included in the file *
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// * LICENSE and available at http://cern.ch/geant4/license . These *
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// * include a list of copyright holders. *
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// * *
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// * Neither the authors of this software system, nor their employing *
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// * institutes,nor the agencies providing financial support for this *
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// * work make any representation or warranty, express or implied, *
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// * regarding this software system or assume any liability for its *
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// * use. Please see the license in the file LICENSE and URL above *
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// * for the full disclaimer and the limitation of liability. *
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// * *
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// * This code implementation is the result of the scientific and *
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// * technical work of the GEANT4 collaboration. *
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// * By using, copying, modifying or distributing the software (or *
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// * any work based on the software) you agree to acknowledge its *
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// * use in resulting scientific publications, and indicate your *
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// * acceptance of all terms of the Geant4 Software license. *
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// ********************************************************************
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//
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// File name: G4VPolarizedCrossSection
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//
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// Author: Andreas Schaelicke
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//
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// Creation date: 15.05.2005
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//
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// Modifications:
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//
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// Class Description:
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// (pure virtual) interface class
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//
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// provides readable but efficient routines to determine
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// polarization for the final state of a given process
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// empoying the differential cross section
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//
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#include "
G4VPolarizedCrossSection.hh
"
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#include "
Randomize.hh
"
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G4VPolarizedCrossSection::G4VPolarizedCrossSection
() :
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fXmin(0), fXmax(1.), fYmin(1.), theA(1), theZ(1), fCoul(0.)
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{
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}
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G4VPolarizedCrossSection::~G4VPolarizedCrossSection
()
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{
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}
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void
G4VPolarizedCrossSection::Initialize
(
G4double
,
G4double
,
G4double
,
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const
G4StokesVector
&,
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const
G4StokesVector
&,
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G4int
)
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{
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}
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G4StokesVector
G4VPolarizedCrossSection::GetPol2
()
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{
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// neglects correlation effects!
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G4double
invXsecTotal=1./
XSection
(
G4StokesVector::ZERO
,
G4StokesVector::ZERO
);
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G4double
xsPol1=
XSection
(
G4StokesVector::P1
,
G4StokesVector::ZERO
);
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G4double
xsPol2=
XSection
(
G4StokesVector::P2
,
G4StokesVector::ZERO
);
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G4double
xsPol3=
XSection
(
G4StokesVector::P3
,
G4StokesVector::ZERO
);
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return
G4ThreeVector
(invXsecTotal*xsPol1,invXsecTotal*xsPol2,invXsecTotal*xsPol3);
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}
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G4StokesVector
G4VPolarizedCrossSection::GetPol3
()
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{
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// neglects correlation effects!
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G4double
invXsecTotal=1./
XSection
(
G4StokesVector::ZERO
,
G4StokesVector::ZERO
);
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G4double
xsPol1=
XSection
(
G4StokesVector::ZERO
,
G4StokesVector::P1
);
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G4double
xsPol2=
XSection
(
G4StokesVector::ZERO
,
G4StokesVector::P2
);
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G4double
xsPol3=
XSection
(
G4StokesVector::ZERO
,
G4StokesVector::P3
);
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return
G4ThreeVector
(invXsecTotal*xsPol1,invXsecTotal*xsPol2,invXsecTotal*xsPol3);
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}
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// minimal energy fraction in TotalXSection
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G4double
G4VPolarizedCrossSection::GetXmin
(
G4double
/*y*/
)
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{
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return
fXmin
;
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}
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// maximal energy fraction in TotalXSection
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G4double
G4VPolarizedCrossSection::GetXmax
(
G4double
/*y*/
)
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{
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return
fXmax
;
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}
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/*
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void G4VPolarizedCrossSection::DicePolarization()
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{
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// can respect correlation effects, but is limited to
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// one quantization axis!
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G4double sigma[4];
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sigma[0]=XSection(G4StokesVector::P3,G4StokesVector::P3);
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sigma[1]=XSection(G4StokesVector::P3,G4StokesVector::M3);
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sigma[2]=XSection(G4StokesVector::M3,G4StokesVector::P3);
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sigma[3]=XSection(G4StokesVector::M3,G4StokesVector::M3);
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G4double sigma_max = 4. * XSection(G4StokesVector::ZERO,G4StokesVector::ZERO);
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for (G4int i=0;i<4;++i) {
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G4cout<<"sigma="<<sigma[i]<<" vs."<<(.25*sigma_max)<<G4endl;
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if (sigma[i]<0 || sigma[i]>sigma_max) {
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G4cout<<"ERROR G4VPolarizedCrossSection::DicePolarization(["<<i<<"]): "
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<<sigma[i]<<" vs."<<sigma_max<<G4endl;
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}
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if (i>0) sigma[i]+=sigma[i-1];
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}
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G4int k = 0;
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G4double disc = sigma[3]*G4UniformRand();
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// Loop checking, 03-Aug-2015, Vladimir Ivanchenko
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while (sigma[k]<disc && k<4) {
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++k;
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}
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if ((k&2)==0) pol2=G4StokesVector::P3;
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else pol2=G4StokesVector::M3;
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if ((k&1)==0) pol3=G4StokesVector::P3;
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else pol3=G4StokesVector::M3;
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}
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*/
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/*
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G4StokesVector G4VPolarizedCrossSection::DicedPol2()
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{
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return pol2;
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}
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G4StokesVector G4VPolarizedCrossSection::DicedPol3()
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{
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return pol3;
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}
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*/
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G4double
G4VPolarizedCrossSection::TotalXSection
(
G4double
,
G4double
,
G4double
,
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const
G4StokesVector
&,
const
G4StokesVector
&)
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{
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G4cout
<<
"WARNING virtual function G4VPolarizedCrossSection::TotalXSection() called"
<<
G4endl
;
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return
0.;
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}
geant4
tree
geant4-10.6-release
source
processes
electromagnetic
polarisation
src
G4VPolarizedCrossSection.cc
Built by
Jin Huang
. updated:
Wed Jun 29 2022 17:25:33
using
1.8.2 with
ECCE GitHub integration