Abstract：
:Gafchromic XRCT, radiochromic film is assessed over a broad energy range, from kilovoltage to megavoltage x rays for variations in reflected optical density to dose response. A large energy dependence was found with reflected optical density output for the same delivered dose varying from 7.8 +/- 0.35 at 25.5 keV (50 kVp) peaking at 12.1 +/- 0.5 at 54 keV (125 kVp) to 0.975 +/- 0.03 at 2300 keV (10 MV) when normalized to 1 at 1400 keV (6 MV) energy. The response is constant (within 3%) in the 36-69 keV equivalent photon energy range, which corresponds to x-ray tube generating potentials of approximately 100-150 kVp. This matches well with beam qualities for diagnostic computed topography applications.
journal_name
Med Physjournal_title
Medical physicsauthors
Butson MJ,Cheung T,Yu PKdoi
10.1118/1.2219330subject
Has Abstractpub_date
2006-08-01 00:00:00pages
2923-5issue
8eissn
0094-2405issn
2473-4209journal_volume
33pub_type
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