Abstract：
:When a beam-modifying filter such as a wedge or a compensator is placed in an x-ray beam, scattered photons are generated in the filter material. The magnitude of the dose contribution from these photons for a 4-MV x-ray beam was measured. At a distance of 30 cm from the filter, a copper sheet of 1-cm thickness produced a dose contribution on the centerline of about 6% of the transmitted primary dose in a 20 X 20 cm2 field. At the edges of the beam, this contribution was only about one-half that on the centerline. The presence of these scattered photons leads to only minor dose errors in clinical applications if simple procedures are followed to account for their contribution.
journal_name
Med Physjournal_title
Medical physicsauthors
Huang PH,Chin LM,Bjärngard BEdoi
10.1118/1.595923subject
Has Abstractpub_date
1986-01-01 00:00:00pages
57-63issue
1eissn
0094-2405issn
2473-4209journal_volume
13pub_type
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