Workshop on Beta-delayed neutron emitters: evaluation and measurements

We explore the systematics of beta-delayed neutron emission probabilities both globally and in regions relevant to applications, such as decay heat calculations. Traditionally, correlations were sought by investigating the P${}_n$ value as a function of the Q value of the decay (or some relation involving Q). Here, we present systematics of the ratio P${}_n$/T{_1/2} and find a strong correlation as a function of the energy available for the beta-delayed neutron decay, $Q_{\beta n}$. Such a relation can be used to predict P${}_n$ values for cases where the half-life is known and could be of relevance to r-process calculations or predictions of advanced fuel cycles. Correlation schemes such as these rely on a precise knowledge of P${}_n$ values. To contribute to the available data, new, precise measurements of P${}_n$ values are planned at the CARIBU facility at Argonne National Laboratory. A brief description of a proof-of-principle case in ${}^{138}$I will be given.