Statistical and dynamical bimodality in multifragmentation reactions

TL;DR

This paper investigates bimodal behavior in nuclear multifragmentation reactions using an enhanced BUU transport model, revealing how different energy regimes and reaction stages contribute to observed bimodality.

Contribution

It introduces a simplified yet accurate BUU model capable of calculating fluctuations in larger systems, linking bimodality to reaction dynamics and energy regimes.

Findings

Bimodal behavior arises from both entrance and exit channel effects.

Dynamical and statistical bimodality are associated with different reaction time scales.

The model explains bimodality across various energy regimes.

Abstract

The bimodal behavior of the order parameter is studied in the framework of Boltzmann-Uehling-Uhlenbeck (BUU) transport model. In order to do that, simplified yet accurate method of BUU model is used which allow calculation of fluctuations in systems much larger than what was considered feasible in a well-known and already existing model. It is observed that depending on the projectile energy and centrality of the reaction, both entrance channel and exit channel effects can be at the origin of the experimentally observed bimodal behavior. Both dynamical and statistical bimodality mechanisms are associated in the theoretical model to different time scales of the reaction, and to different energy regimes.