RADIATION PHYSICS AND CHEMISTRY, vol.80, no.8, pp.855-862, 2011 (SCI-Expanded)
The effective atomic numbers of some compounds including Pb, Th and U as constituents have been calculated for total photon interaction (Z(pleff)) and photon energy absorption (Z(pEAeff)) in the energy region from 1 keV to 20 MeV. It is also seen that the fast neutron removal cross-sections of these compounds have been calculated by using the MERCSF-N computer program. Effective atomic numbers Z(pleff) of compounds have been calculated using two different methods in the continuous energy range and also a single value of Z(pleff) has been obtained via XMuDat computer program. It is recommended that Z(PEAeff) should be used rather than Z(pleff) at the energies where significant differences occur between Z(pleff) and Z(PEAeff) when the interested physical quantity is the energy deposition. The obtained Z(pleff) values using direct and interpolation methods agree well in the intermediate energy region where Compton scattering is predominant whereas in the low and high energy regions they do not agree. The Z(pleff), values calculated by XMuDat were found to agree with the ones obtained using direct method in the low energy region where photoelectric absorption is predominant. Among the compounds, Th(NO3)(4)center dot 5H(2)O, ThF4 center dot 4H(2)O, UO4 center dot 2H(2)O, Th(OH)(4) and PbNO3 have higher values of fast neutron removal cross-sections, thus can be preferred as fast neutron absorber as well as high energy photon absorber. (C) 2011 Elsevier Ltd. All rights reserved.