The neutron dosimetrical parameters, i.e., the fission neutron spectrumaveraged cross-sections and the fluence-to-dose conversion factors have been calculated for some threshold detectors with the aid of a computer. The threshold detectors under investigation were the ^(115)In(n,n´)^(115m)In, ^(22)S(n,p)^(22)p and ^(27)Al(n,α)^(24)Na reactions.
It is revealed that the average cross-sections (σ-) for the ^(22)S(n,p)^(22)p reaction are independent of the spectral functions, namely, the Watt-Cranberg and Maxwellian forms. In the case of the ^(27)Al(n,α)^(24)Na reaction a variation of the σ- values appears to be highly dependent on the fissioning types.
It seems that both the average cross-section for the ^(115)In(n,n´)^(11m)In reaction and the conversion factor are. insensitive to the spectral deformation of fission neutrons. These phenomena make it applicable to use indium as a possible integral fast neutron dosimeter in nuclear criticality accidents provided that the virgin fission neutrons are completely free from the scattered neutrons.
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