Abstract：
:Depth dose distributions for a d(14)Be neutron beam, measured separately for total and gamma absorbed dose, are presented for nine tissue substitutes and for two field sizes. These data are used to examine methods to transform depth dose curves from one material to another. Best results are found when the local depths are transformed by constant empirical factors which are independent of depth and field size. As a physical interpretation of the empirical factors, kerma-weighted mean-free-path lengths are calculated for the interaction of the Essen neutron beam with the materials. The ratios of these free path lengths agree with the empirical factors within +/- 10%. However, for clinical dosimetry, a direct comparability of spatial absorbed dose distributions measured in two different phantom materials is only given if their corresponding transformation factor is near unity.
journal_name
Med Physjournal_title
Medical physicsauthors
Hensley FW,Rassow J,Temme Adoi
10.1118/1.595695subject
Has Abstractpub_date
1985-05-01 00:00:00pages
350-6issue
3eissn
0094-2405issn
2473-4209journal_volume
12pub_type
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