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Geant4 Physics Validation and Verification Ions. Koi, Tatsumi SLAC/SCCS. High Precision neutron down to thermal energy Elastic Inelastic Capture Fission. Evaporation. Evaporation. Pre- compound. Pre- compound. FTF String (up to 20 TeV). Fermi breakup. Fermi breakup. Multifragment. - PowerPoint PPT Presentation
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Geant4 Physics Validation Geant4 Physics Validation and Verificationand Verification
IonsIons
Koi, Tatsumi SLAC/SCCSKoi, Tatsumi SLAC/SCCS
Thermal 1 MeV 10 MeV 100 MeV 1 GeV 10 GeV 100 GeV 1 TeV (/n)
LEP
HEP ( up to 15 TeV)
Photon EvapMultifragmentFermi breakup
Fission
EvaporationPre-
compound
Bertini cascade
Binary cascadeQG String (up to 100 TeV)
FTF String (up to 20 TeV)
High Precision neutron
down to thermal energyElastic
InelasticCaptureFission
LE pp, pn
Rad. Decay
Neutron & Ion Models Inventory
Binary cascade Light IonsPhoton EvapMultifragmentFermi breakup
EvaporationPre-
compound
Rad. Decay
Neutrons
Ions
Wilson Abrasion&Ablation
Electromagnetic Disosiation
Ion PhysicsIon PhysicsInelastic ReactionsInelastic Reactions
• Cross SectionsCross Sections– Tripathi, Shen, Kox and Sihver FormulaTripathi, Shen, Kox and Sihver Formula
• ModelModel– G4BinaryLightIonG4BinaryLightIon– G4WilsonAbrasionG4WilsonAbrasion
Cross SectionsCross Sections
• Many cross section formulae for NN collisions are includeMany cross section formulae for NN collisions are included in Geant4d in Geant4– Tripathi Formula NASA Technical Paper TP-3621 (1997)Tripathi Formula NASA Technical Paper TP-3621 (1997)– Tripathi Light System NASA Technical Paper TP-209726 (1999) Tripathi Light System NASA Technical Paper TP-209726 (1999) – Kox Formula Phys. Rev. C 35 1678 (1987)Kox Formula Phys. Rev. C 35 1678 (1987)– Shen Formula Nuclear Physics. A 49 1130 (1989)Shen Formula Nuclear Physics. A 49 1130 (1989)– Sihver Formula Phys. Rev. C 47 1225 (1993)Sihver Formula Phys. Rev. C 47 1225 (1993)
• These are empirical and parameterized formulae with theThese are empirical and parameterized formulae with theoretical insights.oretical insights.
• G4GeneralSpaceNNCrossSection was prepared to assist G4GeneralSpaceNNCrossSection was prepared to assist users in selecting the appropriate cross section formula.users in selecting the appropriate cross section formula.
Inelastic Cross SectionInelastic Cross SectionC12 on C12C12 on C12
Binary Cascade Binary Cascade ~Model Principals~~Model Principals~
• In Binary Cascade, each participating nucleon is seen as In Binary Cascade, each participating nucleon is seen as a Gaussian wave packet, (like QMD)a Gaussian wave packet, (like QMD)
• Total wave function of the nucleus is assumed to be direTotal wave function of the nucleus is assumed to be direct product of these. (no anti-symmetrization)ct product of these. (no anti-symmetrization)
• This wave form have same structure as the classical HaThis wave form have same structure as the classical Hamilton equations and can be solved numerically.milton equations and can be solved numerically.
• The Hamiltonian is calculated using simple time indepenThe Hamiltonian is calculated using simple time independent optical potential. (unlike QMD)dent optical potential. (unlike QMD)
xtip
tqxLLtpqx ii
ii 2
43
2exp2,,,
Binary Cascade Binary Cascade ~nuclear model ~~nuclear model ~• 3 dimensional model of the nucleus is constructed f3 dimensional model of the nucleus is constructed f
rom A and Z.rom A and Z.• Nucleon distribution followsNucleon distribution follows
– A>16 Woods-Saxon modelA>16 Woods-Saxon model– Light nuclei harmonic-oscillator shell modelLight nuclei harmonic-oscillator shell model
• Nucleon momenta are sampled from 0 to Fermi moNucleon momenta are sampled from 0 to Fermi momentum and sum of these momenta is set to 0.mentum and sum of these momenta is set to 0.
• time-invariant scalar optical potential is used.time-invariant scalar optical potential is used.
Binary Cascade Binary Cascade ~ G4BinaryLightIonReaction ~~ G4BinaryLightIonReaction ~
• Two nuclei are prepared according to this model (previoTwo nuclei are prepared according to this model (previous page).us page).
• The lighter nucleus is selected to be projectile.The lighter nucleus is selected to be projectile.• Nucleons in the projectile are entered with position and Nucleons in the projectile are entered with position and
momenta into the initial collision state.momenta into the initial collision state.• Until first collision of each nucleon, its Fermi motion is Until first collision of each nucleon, its Fermi motion is
neglected in tracking.neglected in tracking.• Fermi motion and the nuclear field are taken into accouFermi motion and the nuclear field are taken into accou
nt in collision probabilities and final states of the collisint in collision probabilities and final states of the collisions.ons.
Neutron Production 400 MeV/n Carbon on Copper
Pion Production
1 GeV/c/n Carbon
on Be, C, Cu and Pn
Geant4 6.2.p02Binary Cascade Light Ions
Distribution of RsDistribution of Rs Carbon Beams Carbon Beams
C 400MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
C 290MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
Target MaterialsIwata et al.,Phys. Rev. C64 pp. 05460901(2001)
R = (σcalculate-σ measure )/σ measure
Overestimate
Underestimate
Distribution of RsDistribution of Rs Neon Beams Neon Beams
Target Materials
Ne 400MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
Ne 600MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)
Distribution of RsDistribution of Rs Argon Beams Argon Beams
Ar 560MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
Target Materials
Ar 400MeV/ n
- 100
0
100
200
0 20 40 60 80
Laboratory Angle [Degree]
Rat
io %
Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)
Neutron YieldNeutron YieldArgon 400 MeV/n beamsArgon 400 MeV/n beams
Carbon Thick Target Aluminium Thick Target
T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
Neutron YieldNeutron YieldArgon 400 MeV/n beamsArgon 400 MeV/n beams
Copper Thick Target Lead Thick Target
T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
Neutron YieldNeutron YieldFe 400 MeV/n beamsFe 400 MeV/n beams
CarbonThick Target Aluminum Thick Target
T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
Neutron YieldNeutron YieldFe 400 MeV/n beamsFe 400 MeV/n beams
Copper Thick Target Lead Thick Target
T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
Distribution of RsDistribution of Rsfor QMD and HIC Calculationfor QMD and HIC Calculation(done by original author)(done by original author)
Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)
100%
Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)
-100%Overestimate
Underestimate
R = 1/σ measure
x(σ measure -σcalculate )
QMD HIC
Fragmented Particles Fragmented Particles ProductionsProductions
Si 490 MeV/ n on C
1
10
100
1000
Al Mg Na Ne F O N C
Particle Species
Cro
ss S
ectio
n [m
b]
DATAG4
Si 490 MeV/ n on H
1
10
100
1000
Al Mg Na Ne F O N C
Particle Species
Cro
ss S
ectio
n [m
b]
DATAG4
F. Flesch et al., J, RM, 34 237 2001
Fragmented Particles Fragmented Particles ProductionsProductions
Si 453 MeV/ n on Al
1
10
100
1000
Al Mg Na Ne F O N C
Particle Species
Cro
ss S
ectio
n [m
b]
DATAG4
Si 490 MeV/ n on Cu
1
10
100
1000
Al Mg Na Ne F O N C
Particle Species
Cro
ss S
ectio
n [m
b]
DATAG4
F. Flesch et al., J, RM, 34 237 2001
Wilson Abrasion & Ablation Wilson Abrasion & Ablation Model Model • G4WilsonAbrasionModel is a simplified macroscopic G4WilsonAbrasionModel is a simplified macroscopic
model for nuclear-nuclear interactions based largely on model for nuclear-nuclear interactions based largely on geometric argumentsgeometric arguments
• The speed of the simulation is found to be faster than The speed of the simulation is found to be faster than models such as G4BinaryCascade, but at the cost of models such as G4BinaryCascade, but at the cost of accuracy.accuracy.
• A nuclear ablation has been developed to provide a A nuclear ablation has been developed to provide a better approximation for the final nuclear fragment from better approximation for the final nuclear fragment from an abrasion interaction. an abrasion interaction.
• Performing an ablation process to simulate the de-Performing an ablation process to simulate the de-excitation of the nuclear pre-fragments, nuclear de-excitation of the nuclear pre-fragments, nuclear de-excitation models within Geant4 (default).excitation models within Geant4 (default).
• G4WilsonAblationModel also prepared and uses the same G4WilsonAblationModel also prepared and uses the same approach for selecting the final-state nucleus as approach for selecting the final-state nucleus as NUCFRG2 (NASA TP 3533)NUCFRG2 (NASA TP 3533)
Abrasion & AblationAbrasion & Ablation
Ablation process
Abrasion process
target nucleus
projectile
Validation of Validation of G4WilsonAbrasionAblation G4WilsonAbrasionAblation modelmodel
12C-C 1050 MeV/nuc
0.1
1.0
10.0
100.0
C11 C10 B11 B10 Be10 Be9 Be7 Li8 Li7 Li6 He6
Fragment
cro
ss-s
ecti
on
[m
b]
Abrasion + ablation
Experiment
NUCFRG2
Ion Physics Ion Physics EelectroMagnetic DissociationEelectroMagnetic Dissociation• Electromagnetic dissociation is liberation of Electromagnetic dissociation is liberation of
nucleons or nuclear fragments as a result of nucleons or nuclear fragments as a result of electromagnetic field by exchange of virtual electromagnetic field by exchange of virtual photons, rather than the strong nuclear photons, rather than the strong nuclear forceforce
• It is important for relativistic nuclear-It is important for relativistic nuclear-nuclear interaction, especially where the nuclear interaction, especially where the proton number of the nucleus is largeproton number of the nucleus is large
• G4EMDissociation model and cross section G4EMDissociation model and cross section are an implementation of the NUCFRG2 are an implementation of the NUCFRG2 (NASA TP 3533) physics and treats this (NASA TP 3533) physics and treats this electromagnetic dissociation (ED).electromagnetic dissociation (ED).
Validation of G4EMDissociaton Validation of G4EMDissociaton Model and Cross SectionModel and Cross Section
Projectile Energy[GeV/nuc]
Product from ED
G4EMDissociation
[mbarn]
Experiment[mbarn]
Mg-24 3.7 Na-23 + p 124 2 154 31
Si-28 3.7 Al-27 + p 107 1 186 56
14.5 Al-27 + p 216 2 165 24†128 33‡
O-16 200 N-15 + p 331 2 293 39†342 22*
Binay CascadeFragmented projectiles C12 on Water
1
10
100
1000
14C
12C
10C 8C 13B
11B 9B 7B
15B
e
13B
e
11B
e
9Be
7Be
5Be
8Li
6Li
4Li
9He
7He
5He
3He
nucleus
Rel
ativ
e in
tens
ity
Arrows indicatednucleus which havehalf life less than10E- 15 sec
C12 on Water Charge Changing Cross SectionBinary Cascade, Secodaries μ >0.5, β >0.9xβ prim
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
100 150 200 250 300 350 400 450
Primary Energy [MeV/ n]
Cro
ss S
ectio
n [b
arn]
0123
Charge Changing Cross Sections
C12 on Water
C12 on Water Charge Changing Cross SectionG4Wilson, Secodaries μ >0.5, β >0.9xβ prim
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
100 150 200 250 300 350 400 450
Primary Energy [MeV/ n]
Cro
ss S
ectio
n [b
arn]
0123
Binary Cascade
G4WilsonBe8s are decayed artificially
Geant4 Validation ListGeant4 Validation List
• 6) o Title: "Thin target neutron productions by Ions intercations"6) o Title: "Thin target neutron productions by Ions intercations"• • o Brief documentation: "Ions beam on different energies incidento Brief documentation: "Ions beam on different energies incident• on different thin target materials produceon different thin target materials produce• neutrons, whose kinetic energy spectra isneutrons, whose kinetic energy spectra is• studied at different angles (i.e. the doublestudied at different angles (i.e. the double• differential cross-sections are measured)."differential cross-sections are measured)."
• o Responsible person: Koi, Tatsumi SLAC/SCCS.o Responsible person: Koi, Tatsumi SLAC/SCCS.
• o Physics List used: Specified one writen by T. K.o Physics List used: Specified one writen by T. K.
• o Process/Model: inelastic ions processes.o Process/Model: inelastic ions processes.• currently only G4BinaryLightIoncurrently only G4BinaryLightIon• future G4WilsonAbrasionfuture G4WilsonAbrasion
• o Level on which the validation/verification is performed: process level.o Level on which the validation/verification is performed: process level.
• o Primary Particles: Carbon12 290 MeV/n, 400 MeV/no Primary Particles: Carbon12 290 MeV/n, 400 MeV/n• Neon20 400 MeV/n, 600 MeV/nNeon20 400 MeV/n, 600 MeV/n• Argon40 400 MeV/n, 600 MeV/nArgon40 400 MeV/n, 600 MeV/n
• o Target materials: Carbon, Copper, Lead.o Target materials: Carbon, Copper, Lead.
• o Observable Values: dobule differential cross sections in [mb/sr/MeV] o Observable Values: dobule differential cross sections in [mb/sr/MeV] • of secondary neutron at 5, 10, 20, 30, 40, 60, 80 deg.of secondary neutron at 5, 10, 20, 30, 40, 60, 80 deg.
• o Data:Double-differential cross sections for the neutron production from o Data:Double-differential cross sections for the neutron production from • heavy-ion reactions at energies E/A = 290-600 MeV. heavy-ion reactions at energies E/A = 290-600 MeV. • Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)Iwata et al.,Phys. Rev. C64 pp. 05460901(2001)
• o Frequency of execution: only once, because of lack of man power.o Frequency of execution: only once, because of lack of man power.
• o Source code availability: Under Preparationo Source code availability: Under Preparation
•
I have 10 more entries for Ions I have 10 more entries for Ions Interactions in G4Validation Interactions in G4Validation List.List.• 6) o Title: "Thin target neutron productions by Ions intercations"6) o Title: "Thin target neutron productions by Ions intercations"• 7) o Title: "Ions hits on several thick target materials and measured 7) o Title: "Ions hits on several thick target materials and measured • 8) o Title: "Pion production cross sections by ions hit on several materials"8) o Title: "Pion production cross sections by ions hit on several materials"• 9) o Title: "Pion production cross sections by carbon hit on carbon"9) o Title: "Pion production cross sections by carbon hit on carbon"• 10)o Title: "Element production cross sections by Iron ion hit on several 10)o Title: "Element production cross sections by Iron ion hit on several • 11)o Title: "Element production cross sections by Silicon ion hit on several 11)o Title: "Element production cross sections by Silicon ion hit on several • 12)o Title: "Fragment production cross sections by Iron ion hit on several 12)o Title: "Fragment production cross sections by Iron ion hit on several • 13)o Title: "Fragment production cross sections by Iron ion hit on several 13)o Title: "Fragment production cross sections by Iron ion hit on several • 14)o Title: "Fragment production cross sections by Iron ion hit on several 14)o Title: "Fragment production cross sections by Iron ion hit on several • 15)o Title: "Fragment production cross sections by carbon hit on carbon"15)o Title: "Fragment production cross sections by carbon hit on carbon"
Summary of validationsSummary of validations
• Neutron DD production and YieldNeutron DD production and Yield– a few hundred MeV/n ~ 400 MeV/na few hundred MeV/n ~ 400 MeV/n– Projectile C12, Ne20, Ar40, Fe56, Xs131Projectile C12, Ne20, Ar40, Fe56, Xs131– Carbon to Lead Target Carbon to Lead Target
• Fragment Particle ProductionFragment Particle Production– a few hundred MeV/n ~ a few GeV/na few hundred MeV/n ~ a few GeV/n– Projectile C12 to Fe56Projectile C12 to Fe56– Carbon to Lead TargetCarbon to Lead Target
• Element ProductionElement Production– 400, 700 MeV/n400, 700 MeV/n– Projectile Si28, Fe56Projectile Si28, Fe56– H, C, Al, Cu, Ag, Pb TargetH, C, Al, Cu, Ag, Pb Target
Areas where not covered by Areas where not covered by models models
• High Energy [>10GeV/n] inelastic High Energy [>10GeV/n] inelastic interactionsinteractions
• Elastic interactions Elastic interactions