Abstract：
:During our routine calibration of a Varian Clinac-20 linear accelerator, the absorbed dose for a fixed monitor unit (mu) was found to decrease with increasing dose rate. Between dose rates of 100 and 500 mu/min, there was up to 20% difference in absorbed dose for a 20-MeV electron beam. The cause of this problem was a failure in the electronics circuit of an integrating board. This paper presents our analysis of the problem and suggests a possible means of isolating such a failure to warn technologists, physicists, and engineers.
journal_name
Med Physjournal_title
Medical physicsauthors
Cheng PC,Kubo Hdoi
10.1118/1.596192subject
Has Abstractpub_date
1988-09-01 00:00:00pages
766-7issue
5eissn
0094-2405issn
2473-4209journal_volume
15pub_type
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