Abstract：
:Ionization chambers of varying inside diameter have been used to investigate the penumbral region of 60Co, 6-MV, and 31-MV x-ray beams. Measurements were made in water at varying depths up to 25 cm for a square field of side length 10 cm. The dependence of the penumbral widths on both the inside diameter of the ionization chamber and the depth in water is established along with the asymmetry of the penumbral distributions about the 50% level. A standard correction is indicated to eliminate the dependence of the measured penumbral widths on the inside diameter of the ionization chamber.
journal_name
Med Physjournal_title
Medical physicsauthors
Dawson DJ,Schroeder NJ,Hoya JDdoi
10.1118/1.595963subject
Has Abstractpub_date
1986-01-01 00:00:00pages
101-4issue
1eissn
0094-2405issn
2473-4209journal_volume
13pub_type
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