DETERMINATION OF RESTRICTED LET DISTRIBUTION FOR MIXED (N,GAMMA) RADIATION-FIELDS BY HIGH-PRESSURE IONIZATION-CHAMBER

A novel method is presented for the determination of the energy loss d istribution in the nanometric region from the initial recombination of ions in high pressure ionisation chambers. Low resolution distributio ns can be obtained by comparison of saturation curves for mixed and re ference gamma radiations. The method was tested using two different io nisation chambers in fields of Am-241-Be, Pu-238-Be and Cf-252 neutron sources. Both the gamma component of the absorbed dose and the qualit y factor calculated from the obtained energy loss distributions agree with the values measured by other methods.