Improved modelling of helium and tritium production for spallation targets

TL;DR

This paper improves the modeling of helium and tritium production in spallation targets by integrating coalescence emission into the INCL4.5-ABLA07 models, resulting in more accurate predictions of light charged particle yields.

Contribution

It introduces enhanced models INCL4.5-ABLA07 that incorporate coalescence emission, significantly improving predictions of helium and tritium production in spallation reactions.

Findings

Coalescence emission is crucial for accurate helium and tritium yield predictions.

INCL4.5-ABLA07 models outperform previous models in predicting light charged particle cross sections.

The new models show good agreement with experimental data across various incident energies.

Abstract

Reliable predictions of light charged particle production in spallation reactions are important to correctly assess gas production in spallation targets. In particular, the helium production yield is important for assessing damage in the window separating the accelerator vacuum from a spallation target, and tritium is a major contributor to the target radioactivity. Up to now, the models available in the MCNPX transport code, including the widely used default option Bertini-Dresner and the INCL4.2-ABLA combination of models, were not able to correctly predict light charged particle yields. The work done recently on both the intranuclear cascade model INCL4, in which cluster emission through a coalescence process has been introduced, and on the de-excitation model ABLA allows correcting these deficiencies. This paper shows that the coalescence emission plays an important role in the tritium and $^3He$ production and that the combination of the newly developed versions of the codes, INCL4.5-ABLA07, now lead to good predictions of both helium and tritium cross sections over a wide incident energy range. Comparisons with other available models are also presented.