Total Reaction Cross Sections in CEM and MCNP6 at Intermediate Energies

TL;DR

This paper evaluates and improves total reaction cross section models in CEM and MCNP6 at intermediate energies, enhancing the accuracy of predictions for applications like space physics and medical physics.

Contribution

It introduces updated cross section models into CEM and MCNP6, replacing outdated ones, leading to more accurate simulation results at intermediate energies.

Findings

Improved cross section models yield better particle spectra predictions.

Enhanced models increase accuracy of total production cross sections.

Results confirm the benefit of updated cross sections in simulations.

Abstract

Accurate total reaction cross section models are important to achieving reliable predictions from spallation and transport codes. The latest version of the Cascade Exciton Model (CEM) as incorporated in the code CEM03.03, and the Monte Carlo N-Particle transport code (MCNP6), both developed at Los Alamos National Laboratory (LANL), each use such cross sections. Having accurate total reaction cross section models in the intermediate energy region ($\sim$50 MeV to $\sim$5 GeV) is very important for different applications, including analysis of space environments, use in medical physics, and accelerator design, to name just a few. The current inverse cross sections used in the preequilibrium and evaporation stages of CEM are based on the Dostrovsky {\it et al.} model, published in 1959. Better cross section models are available now. Implementing better cross section models in CEM and MCNP6 should yield improved predictions for particle spectra and total production cross sections, among other results. Our current results indicate this is, in fact, the case.