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Geant4 Physics Validation and Verification Ions Koi, Tatsumi SLAC/SCCS
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Thermal 1 MeV 10 MeV 100 MeV 1 GeV 10 GeV 100 GeV 1 TeV (/n) LEP HEP ( up to 15 TeV) Photon Evap Multifragment Fermi breakup Fission Evaporation Pre- compound Bertini cascade Binary cascade QG String (up to 100 TeV) FTF String (up to 20 TeV) High Precision neutron down to thermal energy Elastic Inelastic Capture Fission LE pp, pn Rad. Decay Neutron & Ion Models Inventory Binary cascade Light Ions Photon Evap Multifragment Fermi breakup Evaporation Pre- compound Rad. Decay Neutrons Ions Wilson Abrasion&Ablation Electromagnetic Disosiation
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Ion Physics Inelastic Reactions Cross Sections Cross Sections –Tripathi, Shen, Kox and Sihver Formula Model Model –G4BinaryLightIon –G4WilsonAbrasion
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Cross Sections Many cross section formulae for NN collisions are included in Geant4 Many cross section formulae for NN collisions are included in Geant4 –Tripathi Formula NASA Technical Paper TP-3621 (1997) –Tripathi Light System NASA Technical Paper TP-209726 (1999) –Kox Formula Phys. Rev. C 35 1678 (1987) –Shen Formula Nuclear Physics. A 49 1130 (1989) –Sihver Formula Phys. Rev. C 47 1225 (1993) These are empirical and parameterized formulae with theoretical insights. These are empirical and parameterized formulae with theoretical insights. G4GeneralSpaceNNCrossSection was prepared to assist users in selecting the appropriate cross section formula. G4GeneralSpaceNNCrossSection was prepared to assist users in selecting the appropriate cross section formula.
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Inelastic Cross Section C12 on C12
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Binary Cascade ~Model Principals~ In Binary Cascade, each participating nucleon is seen as a Gaussian wave packet, (like QMD) In Binary Cascade, each participating nucleon is seen as a Gaussian wave packet, (like QMD) Total wave function of the nucleus is assumed to be direct product of these. (no anti-symmetrization) Total wave function of the nucleus is assumed to be direct product of these. (no anti-symmetrization) This wave form have same structure as the classical Hamilton equations and can be solved numerically. This wave form have same structure as the classical Hamilton equations and can be solved numerically. The Hamiltonian is calculated using simple time independent optical potential. (unlike QMD) The Hamiltonian is calculated using simple time independent optical potential. (unlike QMD)
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Binary Cascade ~nuclear model ~ 3 dimensional model of the nucleus is constructed from A and Z. 3 dimensional model of the nucleus is constructed from A and Z. Nucleon distribution follows Nucleon distribution follows –A>16 Woods-Saxon model –Light nuclei harmonic-oscillator shell model Nucleon momenta are sampled from 0 to Fermi momentum and sum of these momenta is set to 0. Nucleon momenta are sampled from 0 to Fermi momentum and sum of these momenta is set to 0. time-invariant scalar optical potential is used. time-invariant scalar optical potential is used.
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Binary Cascade ~ G4BinaryLightIonReaction ~ Two nuclei are prepared according to this model (previous page). Two nuclei are prepared according to this model (previous 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 momenta into the initial collision state. Nucleons in the projectile are entered with position and momenta into the initial collision state. Until first collision of each nucleon, its Fermi motion is neglected in tracking. Until first collision of each nucleon, its Fermi motion is neglected in tracking. Fermi motion and the nuclear field are taken into account in collision probabilities and final states of the collisions. Fermi motion and the nuclear field are taken into account in collision probabilities and final states of the collisions.
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Neutron Production 400 MeV/n Carbon on Copper Pion Production 1 GeV/c/n Carbon on Be, C, Cu and Pn Geant4 6.2.p02 Binary Cascade Light Ions
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Distribution of Rs Carbon Beams Target Materials Iwata et al., Phys. Rev. C64 pp. 05460901(2001) R = (σ calculate -σ measure )/σ measure Overestimate Underestimate
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Distribution of Rs Neon Beams Target Materials Iwata et al., Phys. Rev. C64 pp. 05460901(2001)
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Distribution of Rs Argon Beams Target Materials Iwata et al., Phys. Rev. C64 pp. 05460901(2001)
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Neutron Yield Argon 400 MeV/n beams Carbon Thick TargetAluminium Thick Target T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
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Neutron Yield Argon 400 MeV/n beams Copper Thick TargetLead Thick Target T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
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Neutron Yield Fe 400 MeV/n beams CarbonThick TargetAluminum Thick Target T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
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Neutron Yield Fe 400 MeV/n beams Copper Thick TargetLead Thick Target T. Kurosawa et al., Phys. Rev. C62 pp. 04461501 (2000)
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Distribution of Rs for QMD and HIC Calculation (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 -σ calculate ) QMD HIC
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Fragmented Particles Productions F. Flesch et al., J, RM, 34 237 2001
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Fragmented Particles Productions F. Flesch et al., J, RM, 34 237 2001
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Wilson Abrasion & Ablation Model G4WilsonAbrasionModel is a simplified macroscopic model for nuclear-nuclear interactions based largely on geometric arguments G4WilsonAbrasionModel is a simplified macroscopic model for nuclear-nuclear interactions based largely on geometric arguments The speed of the simulation is found to be faster than models such as G4BinaryCascade, but at the cost of accuracy. The speed of the simulation is found to be faster than models such as G4BinaryCascade, but at the cost of accuracy. A nuclear ablation has been developed to provide a better approximation for the final nuclear fragment from an abrasion interaction. A nuclear ablation has been developed to provide a better approximation for the final nuclear fragment from an abrasion interaction. Performing an ablation process to simulate the de- excitation of the nuclear pre-fragments, nuclear de- excitation models within Geant4 (default). Performing an ablation process to simulate the de- excitation of the nuclear pre-fragments, nuclear de- excitation models within Geant4 (default). G4WilsonAblationModel also prepared and uses the same approach for selecting the final-state nucleus as NUCFRG2 (NASA TP 3533) G4WilsonAblationModel also prepared and uses the same approach for selecting the final-state nucleus as NUCFRG2 (NASA TP 3533)
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Abrasion & Ablation Ablation process Abrasion process target nucleus projectile
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Validation of G4WilsonAbrasionAblation model
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Ion Physics EelectroMagnetic Dissociation Electromagnetic dissociation is liberation of nucleons or nuclear fragments as a result of electromagnetic field by exchange of virtual photons, rather than the strong nuclear force Electromagnetic dissociation is liberation of nucleons or nuclear fragments as a result of electromagnetic field by exchange of virtual photons, rather than the strong nuclear force It is important for relativistic nuclear-nuclear interaction, especially where the proton number of the nucleus is large It is important for relativistic nuclear-nuclear interaction, especially where the proton number of the nucleus is large G4EMDissociation model and cross section are an implementation of the NUCFRG2 (NASA TP 3533) physics and treats this electromagnetic dissociation (ED). G4EMDissociation model and cross section are an implementation of the NUCFRG2 (NASA TP 3533) physics and treats this electromagnetic dissociation (ED).
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Validation of G4EMDissociaton Model and Cross Section ProjectileEnergy [GeV/nuc] Product from ED G4EM Dissociation [mbarn] Experiment [mbarn] Mg-243.7Na-23 + p 124 2154 31 Si-283.7Al-27 + p 107 1186 56 14.5Al-27 + p 216 2165 24 † 128 33 ‡ O-16200N-15 + p 331 2293 39 † 342 22*
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Charge Changing Cross Sections C12 on Water Binary Cascade G4Wilson Be8s are decayed artificially
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Geant4 Validation List
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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 incident o Brief documentation: "Ions beam on different energies incident on different thin target materials produce on different thin target materials produce neutrons, whose kinetic energy spectra is neutrons, whose kinetic energy spectra is studied at different angles (i.e. the double studied 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 G4BinaryLightIon currently only G4BinaryLightIon future G4WilsonAbrasion future 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/n o Primary Particles: Carbon12 290 MeV/n, 400 MeV/n Neon20 400 MeV/n, 600 MeV/n Neon20 400 MeV/n, 600 MeV/n Argon40 400 MeV/n, 600 MeV/n Argon40 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 Preparation o Source code availability: Under Preparation
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I have 10 more entries for Ions Interactions in G4Validation 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"
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Summary of validations Neutron DD production and Yield Neutron DD production and Yield – a few hundred MeV/n ~ 400 MeV/n – Projectile C12, Ne20, Ar40, Fe56, Xs131 –Carbon to Lead Target Fragment Particle Production Fragment Particle Production –a few hundred MeV/n ~ a few GeV/n –Projectile C12 to Fe56 –Carbon to Lead Target Element Production Element Production –400, 700 MeV/n –Projectile Si28, Fe56 –H, C, Al, Cu, Ag, Pb Target
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Areas where not covered by models High Energy [>10GeV/n] inelastic interactions High Energy [>10GeV/n] inelastic interactions Elastic interactions Elastic interactions
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