Model for the Glauber-type calculations of beam fragmentation at low energies

TL;DR

This paper develops a modified Glauber model to accurately calculate the momentum distributions of nuclei produced in low-energy heavy ion fragmentation, accounting for energy conservation and reaction geometry.

Contribution

A new theoretical approach based on a modified Glauber model is introduced for low-energy nuclear fragmentation, incorporating energy and momentum conservation laws.

Findings

The model predicts asymmetric longitudinal momentum distributions at low energies.

Distributions depend on reaction geometry and energy, matching experimental trends.

Comparison shows improved accuracy over existing parametrizations.

Abstract

In the present paper momentum distributions of nuclei produced in the heavy ion beam fragmentation at the relatively low energies (below 100 $A\cdot$MeV) are studied. For this study, a new theoretical approach is developed on the basis of the Glauber model modified for taking into account the energy and momentum conservation laws. In this approach, the longitudinal momentum of the most neutron rich nuclei, $^{10}$Be, $^9$Li, $^8$He, produced in a few neutron removal reactions in the $^{11}$B fragmentation in the Be target at a beam energy of 35 $A\cdot$MeV are calculated. The region of applicability of the new approach is discussed. This approach gives the asymmetric longitudinal momentum distributions at low energies, and the asymmetry is defined by the kinematical locus and geometry of the reaction (central of peripheral reactions). We analyze the changes of the phase volume and the longitudinal momentum distributions with the beam energy and number of the removed nucleons. The results of the calculations are compared to the parametrizations widely used for estimates of nuclear production in fragmentation for planning of nuclear experiments.