FLUKA release 2006.3

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FLUKA release 2006.3

• Alfredo.Ferrari_at_cern.ch
• CERN, Geneva, Switzerland
• Sept. 2006

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Major steps since March 2005

• May 2005 definition and approval of the FLUKA
  license
• July 2005 release of FLUKA 2005.6 release of
  the FLUKA source code for INFN and CERN
  researchers
• October 2005 Publication of the FLUKA
  description and user guide as a CERN yellow
  report ( CERN-2005-010)
• September 2006 Release of FLUKA 2006.3

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Highlights from FLUKA 2005.6 release notes

• Elimination of the PEMF preprocessor
• Radioactive products online evolution and
  associated remnant dose calculation
• Electromagnetic dissociation for heavy ions
• New photon cross sections (EPDL97)
• New/updated photon interaction models
• Interface to DPMJET-3 ( 2.53 already available)
• Use of parentheses in the geometry
• Extension of the PEANUT hadronic generator to
  anti-nucleons and extension of its energy range

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New Release FLUKA 2006.3

• Major new features (see release notes for
  details)
• Input by names
• Generation of primary ionisation events (request
  by ALICE)
• New high-energy hadronic generator (available as
  option, it will become the default)
• Improvements in the evaporation/fission models
• First implementation of photon-muon pair
  production
• An initial implementation of the BME model for
  low energy nucleus-nucleus interactions
  (available on request)
• ß/- spectra now include Coulomb and screening
  corrections

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New Release FLUKA 2006.3, cont.

• Major new features (see release notes for
  details)
• Speed up of radionuclide evolution
• Residual nuclei scoring now includes protons as
  well in order to help in gas production scoring
• Optimization algorithm for parentheses
  implemented
• Possibility of implementing the transformations
  required by LATTICE cards using standard ROT-DEFI
  cards

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PEANUT

• PreEquilibrium Approach to NUclear Thermalization
• PEANUT handles hadron-nucleus interactions from
  threshold(or 20 MeV neutrons) to 5 GeV
• Sophisticated Generalized IntraNuclear Cascade
• Smooth transition (all non-nucleons
  emitted/absorbed/decayed all secondaries below
  30-50 MeV)
• Prequilibrium stage
• Standard Assumption on exciton number or
  excitation energy
• Common FLUKA Evaporation model

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The old High Energy interaction model

• Asymptotic Glauber-Gribov cascade implemented in
  the framework of DPM, limited only by energy
  availability
• No explicit account for QuasiElastic (incoherent
  elastic) interactions considered as part of the
  elastic (with a proper slope)
• Simplified intranuclear cascade limited to the
  slowest baryons of each Glauber collision (a sort
  of asymptotic formation zone regime)
• No preequilibrium stage

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Extension of PEANUT

• Peanut has proven to be a precise and reliable
  tool for intermediate energy hadron-nucleus
  reactions
• Its nuclear environment is also used in the
  modelization of (real and virtual) photonuclear
  reactions, neutrino interactions, nucleon decays,
  muon captures..

• The goal was to extend it to cover all the energy
  range, and substitute the high energy h-A
  generator with the following advantages

• Sophisticated (G)INC ? better nuclear physics,
  particularly for residual production
• Smooth transition from intermediate to high
  energies
• Preequilibrium stage
• Explicit formation zone
• Possibility to account explicitly for QuasiElastic

Only two ingredients were missing

1. The treatment of Glauber multiple scattering
2. A continuous and self consistent approach to the
   Quasi-Elastic reaction component

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The Transition

• Low energy the single collision regime
  (Elt?5GeV)
• The first interaction involves one target nucleon
  (exc. pions)
• Quasi-Elastic is a considered as a contribution
  to non-elastic
• QE fraction comes from single nucleon cross
  section ratio
• Mass effects and energy losses are essential

• High energy the Glauber regime (Egt?10 GeV)
• The first interaction involves many target
  nucleons coherently
• Quasi-Elastic cross section separated from
  non-elastic ? (experimentally is added to
  elastic)
• QE is suppressed since h-N inelastic is
  integrated over the projectile path in the
  nucleus
• Mass effects, energy losses, are small

Q.Eelastic interaction at the hadron-nucleon
level
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Problems

• Physics issues
• Transition from ordinary to Glauber cascade
• Consistent approach for Quasi-elastic
  interactions in the Glauber regime
• Self-Consistent approach for inelastic screening
  in the Glauber calculus
• Onset of the formation zone (independent of
  Glauber, but somewhat related)

• Practical issue
• Experimental non-elastic cross sections at
  intermediate and high energies what do they
  really measure?

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Glauber cross sections with self-consistent
inelastic screening corrections (R.Engel)

• Total, Elastic, Quasi-Elastic and absorption
  cross sections computed from proton and neutron
  densities hadron eikonal scattering amplitudes

the correction due to the neglect of diffractive
scattering in the Glauber calculus
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Preliminary cross section results (R.Engel)
Proton Carbon cross section without inelastic
screening
with inelastic screening accounted for in
self-consistent way
Please note the ambiguity of the non-elastic exp.
results, almost 2-population like
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Setting the formation zone yes Glauber, yes
formation zone
Positive Negative ?
Positive Negative ?
Rapidity distribution of charged particles
produced in 250 GeV ? collisions on Aluminum
(left) and Gold (right) Points exp. data (
Agababyan et al., ZPC50, 361 (1991)).
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Old HE model (left) vs new (PEANUT extended)
Positive Negative ?
Positive Negative ?
Rapidity distribution of charged particles
produced in 250 GeV ? collisions on
Aluminum Points exp. data ( Agababyan et al.,
ZPC50, 361 (1991)).
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Old HE model (left) vs new (PEANUT extended)
Positive Negative ?
Positive Negative ?
Rapidity distribution of charged particles
produced in 250 GeV ? collisions on Gold Points
exp. data ( Agababyan et al., ZPC50, 361 (1991)).
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New high-energy generator
The accurate and reliable low energy
generator, PEANUT, has been extended with the
inclusion of Glauber multiple interactions
Data from the HARP experiment at CERN First
published results 12.9 GeV/c p on Al, ?
production vs emission energy and angle
presented at COSPAr2006, Beijing july 006
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New generator NA49 p on C
Double differential ? ?- production for p C
interactions at 158 GeV/c, as measured by NA49
(symbols) and predicted by FLUKA (histograms)
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Example of new fission/evaporation

• The overall result in the residual predictions in
  the spallation zone
• Striking improvement for actinides (which was
  poor before)
• Nice improvement for non-actinides (Pb, Au etc,
  it was already not bad)
• Global improvement in the mass distribution of
  fission fragments for all.
• For non fissionable light-medium mass nuclei
  differences are minorSmooth out some features
  and in particular some excessive odd-even effect

1 A GeV 208Pb p reactions Nucl. Phys. A 686
(2001) 481-524

• Data
• Old FLUKA
• New FLUKA
• New only when exp data exists

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Example of Activity maps
Activation of the n-ToF target 8.41011 p/s 20
GeV/c 6 months irradiation/ 6 months off from
Apr2001 to Oct2004 Cooling down till May 2006
Side view (averaged over 80 cm width )
Front view (averaged over 60 cm length )
Lead target, Steel support, immersed in
cooling/moderating water
Simulations from E. Lebbos et al.,  CERN nTOF
Facility Résultats de la simulation de
l'activité de la cible de n-TOF EET internal
report
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The FLUKA team (AB-ATB-EET)

• 4 staff (M.Brugger, F.Cerutti, A.Ferrari,
  V.Vlachoudis) 2 fellows (L.Sarchiapone,
  M.Mauri), 2 PhD (F.Sommerer, L.Lari)
• Direct responsibility for all FLUKA
  accelerator-related simulations
• Consultancy and support for FLUKA applications in
  RP and PH
• Specific past and present tasks
• IR7 machine protection and damage to electronics
• IR4 radiation damage and shielding
• Machine protection elements (TCDQ, TDI, TCDD)
• CNGS physics, engineering, optimization,
  radiation protection
• n_TOF physics and engineering
• Code development

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Bragg peaks vs exp. data 20Ne _at_ 670 MeV/n
Dose vs depth distribution for 670 MeV/n 20Ne
ions on a water phantom. The green line is the
FLUKA prediction The symbols are exp data from
LBL and GSI
Exp. Data Jpn.J.Med.Phys. 18, 1,1998
Fragmentation products
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On-going developments

• New QMD model for nucleus-nucleus interactions
  0.1-1GeV/A already interfaced, initialization
  database and validation to be completed
• New neutron library well advanced
• Finalization of BME
• new Compton model , last technical details
• Glauber calculations of QuasiElastic
  hadron-nucleus cross section last step
  necessary to have the new high energy generator
  as a default
• Graphical user interface ROOT-based

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The new QMD model examples
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• END