Extension of Intra-Nuclear Cascade Model to Neutron Induced Nonelastic Cross-Sections in Low Energy Region

TL;DR

This paper extends the intra-nuclear cascade model to accurately describe neutron induced nonelastic cross-sections across a broad energy range, capturing both the slow slope and sharp drop features observed experimentally.

Contribution

The authors develop an extended INC model incorporating ground state construction, effective nucleon cross-sections, and quantum effects to explain cross-section behaviors from 100MeV to 1MeV.

Findings

The extended INC reproduces the slow slope of cross-sections from 100MeV to 10MeV.

Quantum effects in the model explain the sharp drop below 10MeV.

The model successfully describes cross-section features down to 1MeV.

Abstract

Two features, a slow slope and a sharp drop, in neutron induced total nonelastic cross-sections are analyzed within the framework of an intra-nuclear cascade (INC) model. First, to reproduce the slow slope from 100MeV to 10 MeV, the original INC is generalized in two points; a method to construct the ground state of the target nucleus, and a method of taking the effective two body cross-sections between two nucleons. Secondly, to analyze the origin of the sharp drop from 10MeV to nearly 1 MeV, the INC is extended to include quantum effects which are originated from the existence of the discrete states in the nuclear potential. It is shown that this extension leads to the sharp drops in the very low energy below around 10MeV. It is concluded that the INC model can be extended to explain the sharp drops in addition to the slow slope in neutron induced nonelastic cross-sections in the energy region from 100MeV down to 1 MeV.