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

Facultat de Física (ECM and ICC), Universitat de Barcelona, Barcelona, Spain.
International Journal of Radiation Biology (Impact Factor: 1.69). 08/2011; 88(1-2):66-70. DOI: 10.3109/09553002.2011.598209
Source: PubMed


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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    • "The dielectric function approach is currently the state-of-the-art for modeling the energy-loss of low-energy electrons in the condensed phase [36] and it is used in most major MC track structure codes, such as OREC/ NOREC [37], PARTRAC [38], PITS [39], KURBUC [40], MC4 [41], RETRACKS [42], and SEICS [43]. Recently, the Dingfelder model [44] for the dielectric function has been implemented into the generalpurpose code PENELOPE for improving electron transport in the lowenergy range [45]. "
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