Revisiting angular momentum conservation in transport simulations of intermediate-energy heavy-ion collisions

TL;DR

This paper investigates the impact of enforcing strict angular momentum conservation in transport simulations of intermediate-energy heavy-ion collisions, revealing effects on density fluctuations, collision rates, and particle production.

Contribution

It introduces a rigorous angular momentum conservation implementation in the IBUU model and compares different prescriptions, highlighting their effects on collision dynamics.

Findings

Angular momentum conservation reduces local density fluctuations.

It influences the collision rate and density evolution.

It affects collective flow and pion production.

Abstract

Based on the well-calibrated IBUU transport model, we have studied the dynamical effect of incorporating rigorous angular momentum conservation in each collision of particles with homework setups. The constraint of the rigorous angular momentum conservation requires in-plane collisions and side jumps of particles after their collision. Since the option is not unique, we have compared two typical prescriptions with the original one. While the results depend quantitatively on the choice of the prescription, we found that the angular momentum conservation generally reduces local density fluctuations and thus the collision rate, and may have some influence on the density evolution, the collective flow, and even the pion production in transport simulations of intermediate-energy heavy-ion collisions.