Abstract：
:A 4-W, laser-based system for the positional readout of thermoluminescent (TL) plates was utilized to obtain dose profiles for a 60Co radiotherapy beam. Experimentally obtained glow curves for LiF resulting from the rapid heating rates characteristic of laser heating agreed well with results predicted using a first-order kinetic model. Excellent system linearity was obtained for sensitivity to 60Co. The useful dynamic range for this tissue-equivalent system could extend over 8 orders of magnitude. A minimum detectable signal of 1.2 R was estimated for the presently configured system, whose spatial resolution is limited by the laser beam diameter, 1.7 mm. Depth dose profiles for the radiotherapy beam obtained using the prototype laser TL system with a specially designed composite 2.2 cm x 3.3 cm x 0.254 mm LiF plate agreed to within 14% of ionization chamber measured doses.
journal_name
Med Physjournal_title
Medical physicsauthors
Kearfott KJ,Grupen-Shemansky MEdoi
10.1118/1.596580subject
Has Abstractpub_date
1990-05-01 00:00:00pages
429-35issue
3eissn
0094-2405issn
2473-4209journal_volume
17pub_type
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