Approximate estimation of effective delayed neutron fraction with correlated sampling method

Nagaya, Yasunobu  ; Nakajima, Ken*

It is needless to say that the effective delayed neutron fraction, which is commonly denoted as , is a very important parameter in reactor kinetics. To estimate the effective delayed neutron fraction in Monte Carlo calculations, we have applied the correlated sampling method, which is one of the Monte Carlo perturbation techniques, to the -ratio method. To verify the proposed methods, we have implemented them into the MVP code and performed a calculation for the effective delayed neutron fraction measured at TCA. It is found that the proposed methods give a good estimate for the effective delayed neutron fraction as well as Nauchi's and Meulekamp's methods.