Investigations of a resonance structure of neutron cross-sections using the multiplicity spectrometry technique

It is known that uncertainties in the calculation of characteristics of power nuclear reactors such as critical sizes, power density field, reactor life time etc are caused mainly (about 40%) by uncertainties in the knowledge of neutron constants of reactor materials. Allowed errors on neutron constants for all basic reactor materials and fission products are about 1-5%. Required errors on constructional materials should be in the range of 5-10% for σt, σs, σγ and from 2 to 12% for self-shielding factors. The required accuracy on neutron constants for the majority of reactor materials is not achieved up to now and consequently it is necessary to continue experimental research in this direction. For example, such an accuracy could be achieved using the multiplicity spectrometry technique of the gamma-rays. The description of this method, its features and several experimental results will be presented.