Photo-fission of 232Th and 238U at intermediate energies

TL;DR

This paper analyzes photon-induced fission of 232Th and 238U at intermediate energies using the CRISP simulation, incorporating a multimodal fission model to predict fragment distributions and fissility.

Contribution

It introduces a multimodal fission extension to the CRISP code and models symmetric and asymmetric fission contributions for photon-induced fission.

Findings

Reproduced fragment mass distribution features.

Calculated charge distribution parameters.

Evaluated fissility of fissioning nuclei.

Abstract

In this work we present an analysis of the yields of fission fragments induced by bremsstrahlung photons with endpoint energies of 50 and 3500 MeV on 232Th and 238U targets using the simulation code CRISP. A multimodal fission option was added to this code and an extension of the calculation to the properties of the fission products is presented. By dividing the fissioning nuclei according to their fissionability, an approach is introduced which accounts for the contribution of symmetric and asymmetric fission. By adopting this procedure, it was possible to calculate the main parameters for the fission fragment charge distribution such as the most probable charge for a given fission product mass chain and its corresponding width parameter. Also, it was possible to reproduce features of fragment mass distribution and evaluate the fissility of fissioning nuclei for photon-induced fission of 232Th and 238U.