PENELOPE: brief overview and benchmark simulations

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PENELOPE brief overview and benchmark simulations

• Francesc Salvat
• José M. Fernández-Varea
• Josep Sempau
• Eduardo Acosta

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What is PENELOPE?
Subroutine package (FORTRAN 77)

• Monte Carlo simulation of the coupled transport
  of e and ?
• Energy range from 100 eV to 1 GeV
• Arbitrary material systems
• Full Class II algorithm
• detailed simulation of ? interactions
• mixed simulation of e interactions

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Photon interactions
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Incoherent (Compton) scattering
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Electron positron interactions
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Bremsstrahlung emission
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Inner-shell ionization by electron impact
Distorted-wave Born approx. cross sections
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Atomic relaxation
Ionization of outer shells (M, N, ) secondary
e no fluorescent radiation
Ionization of inner shells (K, L1, L2,
L3) secondary e fluorescent radiation (x-ray
or Auger e )
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Mixed simulation algorithm
Hard collisions ? gt? c , W gtWc soft events ?
lt? c , W ltWc
Recipe
Then, in a step of length
we have (on average)
and
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Random-hinge method

• Multiple-scattering moments are accurately
  reproduced
• Easy to implement for the MW DCS
• Interface crossing poses no difficulty
• The energy dependence of Ss and ?s2 is easily
  implemented
• Variation of the hard mfp with energy is
  accounted for by fictitious ? interactions
  (defining smax)
• Angular deflections in soft inelastic events are
  incorporated

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Stability (i)
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Stability (ii)
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Auxiliary tools

• Geometry package PENGEOM
• Geometry viewers
• Variance-reduction techniques
• Simulation in static electric magnetic fields
• Program SHOWER

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Benchmark simulations
Backscattering coefficients
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Energy distributions of backscattered electrons
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Transmission coefficients
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Positron implantation
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Depth-dose functions
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Bremsstrahlung photon energy distributions
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EPMA x-ray spectra
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Summary

• Freely available from the NEA Data Bank
• http//www.nea.fr
• We have written ample documentation
• http//www.nea.fr/lists/penelope.html
• Over 200 copies of the program have been
  distributed
• PENELOPE is the basis of multiple papers and PhD
  theses
• Some of the models will be implemented in Geant4