Abstract：
:Routine constancy checks of electron energy are often time consuming because of the necessity to measure a dose at two depths. A technique is described that uses a double-wedge shaped phantom positioned on a Profiler diode array for measuring an electron energy constancy metric similar to R(50). The double-wedge electron profiles are invariant to phantom alignment in the wedge direction, unlike single wedge techniques, and the sensitivity of the technique is similar to water-based depth-dose measurements over an energy range of 6 to 20 MeV. Reproducibility results ranging from 0.01 to 0.03 cm were achieved for measurements taken over the course of 1.5 yrs. The technique is efficient in that only one phantom setup is required for all electron energies.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Wells DM,Picco PJ,Ansbacher Wdoi
10.1120/jacmp.v4i3.2516keywords:
subject
Has Abstractpub_date
2003-07-01 00:00:00pages
204-8issue
3issn
1526-9914journal_volume
4pub_type
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