Validity of spherical approximations of initial charge cloud shape in silicon detectors
2011 (English)In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, Vol. 648, no SUPPL. 1, 190-193 p.Article in journal (Refereed) Published
Spherical approximation has been used extensively in low-energy X-ray imaging to represent the initial charge cloud produced by photon interactions in silicon detectors, mainly because of its simplicity. However, for high-energy X-rays, where the initial charge distribution is as important as the diffusion process, the spherical approximation will not result in a realistic detector response. In this paper, we present a bubble-line model that simulates the initial charge cloud in silicon detectors for photons in the energy range of medical imaging. An initial charge cloud can be generated by sampling the center of gravity and the track size from statistical distributions derived from Monte Carlo generated tracks and by distributing a certain proportion of photon energy into a bubble (68%) and a line portion uniformly. The simulations of detector response demonstrate that the new model simulates the detector response accurately and corresponds well to Monte Carlo simulation.
Place, publisher, year, edition, pages
2011. Vol. 648, no SUPPL. 1, 190-193 p.
Spherical approximation; Statistical model; Monte Carlo simulation; Signal induction; Silicon
Other Physics Topics
IdentifiersURN: urn:nbn:se:kth:diva-47662DOI: 10.1016/j.nima.2010.11.173ISI: 000305376900049ScopusID: 2-s2.0-79960835983OAI: oai:DiVA.org:kth-47662DiVA: diva2:455935
QC 201111152011-11-112011-11-112012-11-23Bibliographically approved