Speaker
Description
In the unresolved resonance region (URR), cross sections for neutrons interacting with nuclei have resonances that cannot be measured nor predicted, hence only statistical values are provided. Often, proper simulations by neutronic transport codes require special data and handling in the URR to account for the variation in the cross sections in this region. The current methodology used to describe this behavior is to construct the probability table of the cross section. This table is generated by extrapolating the average resonance widths and average resonance spacings from the resonance region, generating Monte Carlo realizations of resonance ladders and using these realizations to construct the probability tables. Although this is a standard and widely used technique, it is computationally very expensive. Therefore, an analytical fit would be preferable due to the considerable speed up of the computational time in real life applications. Since the only input for these tables is the average resonance parameters, which are functions of energy, orbital angular momentum, and total angular momentum, our hypothesis is that the probability tables might display a “universal” form for each reaction channel regardless of the nuclear species. If this is true, a single functional form per reaction channel could be used to parametrize the probability table for every nucleus. To test this hypothesis, our goal is to generate probability tables for different spin groups, different reaction channels, and different nuclei. As a first step, these tables will be analyzed searching for regularities and, if our hypothesis proves correct, as a second step we will use modern computational techniques to produce accurate analytical fits for each spin group.