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G4UCNAbsorption.cc
Go to the documentation of this file.
Or view
the newest version in sPHENIX GitHub for file G4UCNAbsorption.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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//
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// UCN Absorption Class Implementation
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//
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// File: G4UCNAbsorption.cc
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// Description: Discrete Process -- Absorption of Ultra Cold Neutrons
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// Version: 1.0
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// Created: 2014-05-12
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// Author: Peter Gumplinger
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// adopted from Geant4UCN by Peter Fierlinger (7.9.04) and
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// Marcin Kuzniak (21.4.06)
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// 1/v energy dependent absorption cross section
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// inside materials
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// Updated:
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//
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// mail: gum@triumf.ca
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//
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#include "
G4UCNProcessSubType.hh
"
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#include "
G4UCNAbsorption.hh
"
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//#include "G4Nucleus.hh"
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//#include "G4ReactionProduct.hh"
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//#include "G4NucleiPropertiesTable.hh"
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#include "
G4SystemOfUnits.hh
"
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#include "
G4PhysicalConstants.hh
"
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// Class Implementation
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// Operators
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// G4UCNAbsorption::operator=(const G4UCNAbsorption &right)
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// {
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// }
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// Constructors
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G4UCNAbsorption::G4UCNAbsorption
(
const
G4String
& processName,
G4ProcessType
type)
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:
G4VDiscreteProcess
(processName, type)
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{
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if
(
verboseLevel
>0)
G4cout
<<
GetProcessName
() <<
" is created "
<<
G4endl
;
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SetProcessSubType
(
fUCNAbsorption
);
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}
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// G4UCNAbsorption::G4UCNAbsorption(const G4UCNAbsorpton &right)
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// {
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// }
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// Destructors
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G4UCNAbsorption::~G4UCNAbsorption
(){}
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// Methods
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// PostStepDoIt
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// -------------
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G4VParticleChange
*
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G4UCNAbsorption::PostStepDoIt
(
const
G4Track
& aTrack,
const
G4Step
& aStep)
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{
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aParticleChange
.
Initialize
(aTrack);
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aParticleChange
.
ProposeTrackStatus
(
fStopAndKill
);
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if
(
verboseLevel
> 0 )
G4cout
<<
"UCNABSORPTION at: "
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<< aTrack.
GetProperTime
()/
s
<<
"s, "
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<< aTrack.
GetGlobalTime
()/
s
<<
"s. "
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<<
", after track length "
<< aTrack.
GetTrackLength
()/
cm
<<
"cm, "
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<<
"in volume "
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<< aStep.
GetPostStepPoint
()->
GetPhysicalVolume
()->
GetName
()
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<<
G4endl
;
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return
G4VDiscreteProcess::PostStepDoIt
(aTrack, aStep);
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}
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// GetMeanFreePath
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// ---------------
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G4double
G4UCNAbsorption::GetMeanFreePath
(
const
G4Track
& aTrack,
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G4double
,
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G4ForceCondition
* )
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{
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G4double
AttenuationLength =
DBL_MAX
;
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const
G4Material
* aMaterial = aTrack.
GetMaterial
();
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G4MaterialPropertiesTable
* aMaterialPropertiesTable =
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aMaterial->
GetMaterialPropertiesTable
();
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G4double
losscs = 0.0;
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if
(aMaterialPropertiesTable) {
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losscs = aMaterialPropertiesTable->
GetConstProperty
(
"ABSCS"
);
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// if (losscs == 0.0)
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// G4cout << "No UCN Absorption length specified" << G4endl;
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}
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// else G4cout << "No UCN Absorption length specified" << G4endl;
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if
(losscs) {
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// Calculate a UCN absorption length for this cross section
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// *** Thermal boost ***
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// Prepare neutron
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//G4double theA = aMaterial->GetElement(0)->GetN();
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//G4double theZ = aMaterial->GetElement(0)->GetZ();
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//G4ReactionProduct
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// theNeutron(const_cast<G4ParticleDefinition *>(aTrack.GetDefinition()));
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//theNeutron.SetMomentum(aTrack.GetMomentum());
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//theNeutron.SetKineticEnergy(aTrack.GetKineticEnergy());
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//G4ThreeVector neuVelo = theNeutron.GetMomentum()/
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// aTrack.GetDefinition()->GetPDGMass());
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// Prepare properly biased thermal nucleus
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//G4double theA = aMaterial->GetElement(0)->GetN();
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//G4double theZ = aMaterial->GetElement(0)->GetZ();
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//G4double eps = 0.0001;
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//G4double eleMass =
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// G4NucleiPropertiesTable::
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// GetNuclearMass(static_cast<G4int>(theZ+eps),
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// static_cast<G4int>(theA+eps)))
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// / G4Neutron::Neutron()->GetPDGMass();
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//G4Nucleus aNuc;
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//G4ReactionProduct aThermalNuc =
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// aNuc.GetBiasedThermalNucleus(eleMass,
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// neuVelo,
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// aMaterial->GetTemperature());
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// Boost to rest system and return
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//G4ReactionProduct boosted;
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//boosted.Lorentz(theNeutron, aThermalNuc);
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//G4double vel = sqrt(2*boosted.GetKineticEnergy()/
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// neutron_mass_c2*c_squared);
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G4double
density = aMaterial->
GetTotNbOfAtomsPerVolume
();
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// Calculate cross section for a constant loss
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G4double
vel = aTrack.
GetVelocity
();
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//G4cout << aTrack.GetVelocity()/meter*second << " "
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// << vel/meter*second << "meters/second" << G4endl;
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// Input data is normally taken from the website:
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// http://rrdjazz.nist.gov/resources/n-lengths/list.html
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// and coresponds to 2200 m/s fast neutrons
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G4double
crossect = losscs*
barn
*2200.*
meter
/
second
/vel;
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// In principle, if one asks for the MaterialProperty incoherent cross
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// section, one could put the formula for inelastic up scattering here
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// and add the cross section to the absorption
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// sigma inelastic = ... ignatovic, p. 174.
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// attenuation length in mm
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AttenuationLength = 1./density/crossect;
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if
(
verboseLevel
>0)
G4cout
<<
"UCNABSORPTION with"
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<<
" AttenuationLength: "
<< AttenuationLength/
m
<<
"m"
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<<
" CrossSection: "
<< crossect/
barn
<<
"barn"
<<
G4endl
;
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}
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return
AttenuationLength;
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}
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geant4-10.6-release
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G4UCNAbsorption.cc
Built by
Jin Huang
. updated:
Wed Jun 29 2022 17:25:51
using
1.8.2 with
ECCE GitHub integration