Abstract:
:New definitions of the absorbed dose conversion factors Clambda and CE are proposed. The absorbed dose in water is given by the product of absorbed dose conversion factor, exposure calibration factor, ionisation chamber reading, cap displacement correction factor and perturbation correction factor. At exposure calibration the material of the build-up cap must be the same as that of the chamber wall. An ionisation chamber of which the wall material is water-equivalent or air-equivalent may be used. In the latter case the wall must be thin. For these two cases absorbed dose conversion factors are introduced and it is recommended that either of the two sets should be adopted. Furthermore, if the chamber wall is neither water- nor air-equivalent, the factor by which these currently defines values should be mutliplied is also given: again the wall must be thin. The ICRU definitions of Clambda and CE are inconsistent, as recently pointed out, while the definitions presented here are consistent.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Shiragai Adoi
10.1088/0031-9155/23/2/003subject
Has Abstractpub_date
1978-03-01 00:00:00pages
245-52issue
2eissn
0031-9155issn
1361-6560journal_volume
23pub_type
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