Community Research and Development Information Service - CORDIS


Cavity chamber absorbed dose measurements do not usually strictly adhere to the conditions of the Fano theorem and therefore corrections must be made to account for differences in the gas and wall mass stopping powers. Values of gas to wall absorbed dose conversion factors were calculated for neutron energies of 25 MeV to 250 MeV for detectors with walls of a variety of elements and compounds and A-150 tissue equivalent (TE) plastic. The use of a filled cavity was also evaluated. The calculations required initial spectral fluences of (1)H, (2)H, (3)He and (4)He ions released by neturon reactions in the walls, and these were calculated with the Los Alamos High Energy Transport code. Mass stopping powers data were taken from Ziegler et al. Additional calculations were made for a few cases in order to test the sensitivity of conversion factors to ion production and mass stopping power input data from other sources. The ALICE nuclear reaction code and the recent ICRU stopping power tabulations were used for these tests.

Additional information

Authors: NEWHAUSER W D, Physikalisch-Technische Bundesanstalt, Braunschweig (DE);SCHREWE U J, Physikalisch-Technische Bundesanstalt, Braunschweig (DE);WIEGEL B, Physikalisch-Technische Bundesanstalt, Braunschweig (DE)
Bibliographic Reference: Report: PTB-N-25 (EN) 1995 37pp.
Availability: Available from Physikalisch Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig (DE)
Record Number: 199610061 / Last updated on: 1996-02-16
Original language: en
Available languages: en