Method of experimental estimation of the effective delayed neutron fraction and of the neutron generation lifetime in the IBR-2 pulsed reactor

Experimental investigations of random fluctuations in the power of the IBR-2 periodic pulsed reactor carried out in the steady-state mode of its operation and in the pulsed mode made it possible to obtain estimations of the main parameters of the kinetics – the effective fraction of delayed neutrons and the average lifetime of prompt neutrons. Functionals were measured relating the main parameters of the kinetic behaviour: the prompt neutron decay constant (steady-state mode) and the relative dispersion of pulse energy fluctuations. It was shown that the experimental values of parameters of the kinetic behaviour are close to the calculated ones. In addition, the power of the spontaneous neutron source was estimated on the basis of the analysis of neutron noise.