Abstract:
:The concepts of radiance and fluence are fundamental to the description of a radiation field. The International Commission on Radiological Units and Measurements (ICRU) has defined fluence in terms of the number of the radiation particles crossing a small sampling sphere. A second definition has been proposed in which the length of track segments contained within any sampling volume are used to calculate the incident fluence. This approach is often used in Monte Carlo simulations of individual particle tracks, allowing the fluence to be scored in small volumes of any shape. In this paper we stress that the second definition generalizes the classical (ICRU) concept of fluence. We also identify the assumptions inherent in the two definitions of fluence and prove their equivalence for the case of straight-line particle trajectories.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Papiez L,Battista JJdoi
10.1088/0031-9155/39/6/011subject
Has Abstractpub_date
1994-06-01 00:00:00pages
1053-62issue
6eissn
0031-9155issn
1361-6560journal_volume
39pub_type
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