# Many-particle correlations and Coulomb effects on temperatures from fragment momentum fluctuations

## TL;DR

This paper examines how Coulomb interactions and many-particle correlations influence temperature measurements derived from fragment momentum distributions in nuclear breakup, proposing correction methods to improve accuracy.

## Contribution

It introduces a combined analytical and simulation-based approach to account for Coulomb effects and correlations in nuclear fragmentation temperature analysis.

## Key findings

- Coulomb effects significantly alter temperature estimates.
- Many-particle correlations are non-negligible and affect temperature measurements.
- Correction methods improve the accuracy of temperature determinations.

## Abstract

We investigate correlations in the fragment momentum distribution due to the propagation of fragments under the influence of their mutual Coulomb field, after the breakup of an excited nuclear source.The magnitude of the effects on the nuclear temperatures obtained from such distributions is estimated with the help of a simple approach in which a charged fragment interacts with a homogeneous charged sphere. The resuslts are used to correct the temperatures obtained from the asymptotic momentum distributions of fragments produced by a Monte-Carlo simulation in which the system's configuration at breakup is provided by the canonical version of the Statistical Multifragmentation Model. In a separate calculation, the dynamics of this many-particle charged system is followed in a molecular dynamics calculation until the fragments are far away from the breakup volume. The results suggest that, although the magnitude of the corrections is similar in both models, many-particle correlations present in the second approach are non-negligible and should be taken into account in order to minimize ambiguities in such studies.