Open AccessMonte Carlo calculation of beam quality correction for solid‐state detectors and phantom scatter correction at 137 Cs energy
Author(s) -
Selvam T. Palani,
Mishra Subhalaxmi,
Vishwakarma R.S.
Publication year - 2014
Publication title -
journal of applied clinical medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.83
H-Index - 48
ISSN - 1526-9914
DOI - 10.1120/jacmp.v15i1.4445
Subject(s) - monte carlo method , imaging phantom , physics , detector , beam (structure) , quality (philosophy) , energy (signal processing) , optics , solid state , laser beam quality , nuclear physics , computational physics , mathematics , statistics , laser beams , engineering physics , laser , quantum mechanics
Beam quality correction k Q Q 0 ( r ) , which reflects the absorbed energy dependence of the detector, is calculated for solid‐state detector materials diamond, LiF, Li 2B 4O 7 , andAl 2O 3for the137 Cs RTR brachytherapy source using the Monte Carlo‐based EGSnrc code system. The study also includes calculation of detector‐specific phantom scatter corrections k p h a n ( r ) for solid phantoms such as PMMA, polystyrene, RW1, solid water, virtual water, and plastic water. Above corrections are calculated as a function of distance r along the transverse axis of the source. k Q Q 0 ( r ) is about unity for the Li 2B 4O 7detector. LiF detector shows a gradual decrease in k Q Q 0 ( r ) with r (decrease is about 2% over the distance range of 1‐15 cm). Diamond detector shows a gradual increase in k Q Q 0 ( r ) with r (about 3% larger than unity at 15 cm). In the case ofAl 2O 3detector, k Q Q 0 ( r ) decreases with r steeply (about 14% over the distance range of 1‐15 cm). The study shows that some solid‐state detectors demonstrate distance‐dependent k p h a n ( r ) values, but the degree of deviation from unity depends on the type of solid phantom and the detector. PACS number: 87.10.Rt, 87.53.Bn, 87.53.Jw, 87.56.Bg