Effect of missing levels on the observed channels open in neutron fission

Abstract

It is shown that the effect of missing small fission widths in the analysis of a fission width distribution is to give an apparent number of channels open greater than the actual number open. This is demonstrated both by a numerical experiment and by analytical considerations. A set of resolution probabilities is postulated such that when the apparent distribution is calculated from the true distribution, the effective number of degrees of freedom increases by a specific amount. The theory is applied to the experimental set of fission widths for neutron fission of 235U in both the J = 3 and 4 states.