ATIC Backscatter Study using Monte Carlo Methods in FLUKA

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ATIC Backscatter Study using Monte Carlo Methods
in FLUKA ROOT

• Thomas Wilson, Lawrence Pinsky,
• Anton Empl, Victor Andersen,
• Joachim Isbert John Wefel (LSU)
• Rene Brun Federico Carminati (CERN)
• Alfredo Ferrari Paola Sala (INFN)

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Summary

• We have conducted a brief study of the neutron
  backscatter albedos in the ATIC balloon payload.
• We have accomplished this using FLUKA as the
  physics engine, and
• We are developing a user interface and analysis
  infrastructure based upon ROOT.
• We have introduced a new converter for
  transforming GEANT3 geometries into FLUKA inputs.

Our website is at http//fleur.cern.ch/project/
index.html
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Background

• FLUKA is a well-known Monte Carlo whose upgrade
  was recently endorsed by INFN (Sept. 2001).
• Our results evolved from simulation tools _at_CERN
  ROOT and ALIROOT (a ROOT-based Virtual
  Monte-Carlo Interface designed to do simulations
  for ALICE at the LHC).
• Our results are part of a NASA investiga-tion
  into next-generation simulation tools for
  materials science applications in space.

ALICE A Large Ion Collision Experiment
AliRoot ALICE ROOT
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FLUKA Changes

• At high energies gt30GeV/A, the Dual Parton Model
  (DPM) is utilized. This study used DPMJET II.5.
  DPMJET III is about to be released. We are
• Adding Heavy-Ion Interactions (all ions from
  A246 in DPMJET down to He including the full
  range of interactions). Below 3 GeV/A there is
  need for improvement, using modified RQMD or
  PEANUT.
• Converting FLUKA input output to a ROOT
  interface (similar to ALIROOT at ALICE LHC).
• Interchanging geometry formats (Empl converter
  used to generate the ATIC GEANT3.21 input
  geometry into FLUKA).

RQMDRel.Quant.Mol.Dyn.
PEANUTPrequil.Approach to Nucl.Thermaliz.
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FLUKA Verification(AMS Data)
Upgoing proton flux FLUKA sim (solid line)
versus AMS (triangles)
Zuccon et al. ICRC-2001 (Hamburg)
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FLUKA Verification(AMS Data)
Downgoing proton flux FLUKA sim (solid line)
versus AMS (triangles)
Zuccon et al. ICRC-2001 (Hamburg)
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ATIC Geometry
Note The I-beams and other external structure
in this early scheme were not used in the
simulation.
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FLUKA ATIC Simulations
Raw Energy Deposition (not corrected for
quenching and other effects)
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FLUKA ATIC Simulations
Raw Energy Deposition (not corrected for
quenching or other effects)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Neutron Fluence (n/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Neutron Balance (Neutrons in Minus out)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Charged Hadron Fluence (particles/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Charged Particle Fluence (particles/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Photon Fluence (photons/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Energy Deposited (GeV/cm3)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Beam Offset - Neutron Fluence (n/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Beam Offset - Neutron Balance (Neutrons in Minus
out)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Offset Beam Charged Hadron Fluence
(particles/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Offset Beam Charged Particle Fluence
(particles/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Offset Beam Photon Fluence (photons/cm2)
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FLUKA ATIC Simulations
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Offset Beam Energy Deposited (GeV/cm3)
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ROOT Versions of .ps files
100 GeV/A Incident Carbon
1 TeV/A Incident Carbon
Neutron Fluence (n/cm2)
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Conclusions

• We have conducted a brief, preliminary study of
  ATIC using a new, enhanced FLUKA.
• We have taken a GEANT3 geometry (ATIC) and re-run
  it using this FLUKA.
• This opens the doorway for re-analysis of all the
  G3 heritage of work with a superior Monte Carlo.
• The neutron and hadron physics of FLUKA is
  particularly suited for backscatter studies of
  instrument and detector designs.
• Eventually the ALIROOT architecture will
  accommodate FLUKA as well G3 and G4. This will
  be by user selection.