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Tricks & tips on the use of PENELOPE

Jos M. Fernndez-Varea

Medicinsk Strlningsfysik, KI & SU October 19th, 2005

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Why PENELOPE?

Other MC codes publicly available:

ETRAN (NIST), ITS3 (Sandia)EGS4 (Stanford), EGSnrc (NRCC)

MCNP (Los Alamos)

Geant4 (CERN)

Main features of PENELOPE (v. 2005):

Coupled electron/photon transport

Energy range 50 eV to 1 GeV

Arbitrary material systemsMixed (class II) simulation

Distributed (free of charge) by the NEA

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Platforms

Total Commander http://www.ghisler.com

g95 fortran compiler

Windows http://g95.sourceforge.netLinux http://www.intel.com

gnuplot http://www.gnuplot.info

Auxiliary software

Windows or Linux

Clive Pages FORTRAN 77 bookhttp://www.star.le.ac.uk/~cgp/fortran.html

Fortran77 syntax checking - FTNCHEKhttp://www.dsm.fordham.edu/%7Eftnchek/

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Documentation

~/penelope/doc/tutorial.pdf

~/penelope/doc/manual.pdf

~/penelope/doc/PENELOPE_2003_NEA.pdf

http://www.nea.fr/lists/penelope.html

Written documentation in the distribution:

NEAs listserver:

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common /TRACK/ E,x,y,z,u,v,w,wght,kpar,ibody,m,ilb(5)Particle state always available through

Random hinge algorithm:

Transport mechanics

hard col.

hard col.

soft event

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Cutoff energies:Eabs(1) absorption energy for electrons

Eabs(2) absorption energy for photons

Eabs(3) absorption energy for positrons

Simulation parameters:C1 limits step length

C2 limits step length

dsmax limits step lengthWcc hard inelastic collisions

Wcr hard bremsstrahlung interactions

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Reduced quadric

Arbitrary quadric = reduced quadric + scale + rotation + shift

Quadric geometry package PENGEOM

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Planes: 1, 2, 3Cones: 4

Cylinders: 5

Spheres: 6

Simple example: arrow in a sphere

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Examples of realistic geometrical structures

Sempau et al, Phys Med Biol46 (2001) 1163

Marre et al, Phys Med Biol45 (2000) 3657

Mazurier et al, Phys Med Bio l46 (2001) 1707

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Mourtada et al, Med Phys30 (2003) 959

Sempau et al, Phys Med Bio l49 (2004) 4427

Al-Dweri et al, Phys Med Biol49 (2004) 2687

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Examples of main programs

Structure of a generic main program

Examples of main program in the distribution:penslab, pencyl,penmain

PENELOPE is a subroutine package

Subroutine STORESmay be needed to sample the source

See pages 7 and 8 of tutorial.pdf

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init

source

sPhiE

score1

result

mcend

score2

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Reducing CPU time

Use of di fferent cutoffs and/or simulation parameters in

different materials

Depth dose profile

0.004

0.006

0.008

0.01

0.012

0.014

0.016

0.018

0 1 2 3 4 5 6 7 8 9 10

z / cm

D/

eV/g

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Variance-reduction techniques:

Interaction forcing

Splitting

Russian roulette

Range rejection

Use of various CPUs:

the clonEasypackage (J. Sempau & A. Badal, UPC)http://www.upc.es/inte/english/download_engALL.htm

call rngrej(Erej,kpbrej,ibrej,mrej)

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