Article

# Limitations (and merits) of PENELOPE as a track-structure code.

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Facultat de Física (ECM and ICC), Universitat de Barcelona, Barcelona, Spain.
(Impact Factor: 1.84). 08/2011; 88(1-2):66-70. DOI: 10.3109/09553002.2011.598209
Source: PubMed

ABSTRACT To outline the limitations of PENELOPE (acronym of PENetration and Energy LOss of Positrons and Electrons) as a track-structure code, and to comment on modifications that enable its fruitful use in certain microdosimetry and nanodosimetry applications.
Attention is paid to the way in which inelastic collisions of electrons are modelled and to the ensuing implications for microdosimetry analysis.
Inelastic mean free paths and collision stopping powers calculated with PENELOPE and two well-known optical-data models are compared. An ad hoc modification of PENELOPE is summarized where ionization and excitation of liquid water by electron impact is simulated using tables of realistic differential and total cross sections.
PENELOPE can be employed advantageously in some track-structure applications provided that the default model for inelastic interactions of electrons is replaced by suitable tables of differential and total cross sections.

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Available from: Mariel Elisa Galassi, Jun 08, 2015
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• "For each simulated photoelectric absorption within a AuNP, the escaping electron and photon tracks were followed in 3D and the local nanoscale energy deposition was recorded using a customized tally. Although PENELOPE has limitations with regards to very low-energy electron inelastic scattering simulation and track structure calculations (Bernal and Liendo 2009, Nikjoo et al 2006), we chose this code due to its comprehensive coupled electron/photon transport simulation through various mediums including tissue and gold, and flexibility of its geometry package (Fernandez-Varea et al 2012). Furthermore, PENELOPE offers a highly customizable code allowing for user defined tallies that were required for this study (Salvat et al 2008). "
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