Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1994-2-22
pubmed:abstractText
The breakdown of Molière's multiple-scattering theory for short pathlengths occurring during Monte Carlo simulations with charged particles is demonstrated. It has been found that in certain conditions where the theory is assumed to be valid, significant distortions of the angular distribution occur that make the sampling of the polar angle questionable in numerous steps of Monte Carlo simulations. The limits of the theory have been investigated, both using a large number of terms in the Molière's series and using steps of Molière's theory where 1/B expansions are not involved. At B = 4.5 the commonly accepted 3-term series expansion yields differences up to +/- 6% compared with the evaluation of the complete Molière angular distribution, and up to 7 terms in the series are needed in order to achieve agreement within +/- 2%. One percent agreement requires B = 10. Numerical values of the full distribution are given in terms of Molière's parameters B and reduced angle theta. By using the general dependence of the distribution results are valid for both electron and proton Monte Carlo simulations in any material.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0094-2405
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1315-25
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:articleTitle
Constraints of the multiple-scattering theory of Molière in Monte Carlo simulations of the transport of charged particles.
pubmed:affiliation
Department of Radiation Physics, University of Lund, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't