# Conserved charge fluctuations using the $D$-measure in heavy-ion collisions

## TL;DR

This study investigates net-charge fluctuations in heavy-ion collisions using the $D$-measure across different models and energies, analyzing effects of acceptance, resonance decay, and particle species to establish a baseline for experimental comparison.

## Contribution

It provides a comparative analysis of $D$-measure fluctuations in HIJING, UrQMD, and HRG models, including effects of acceptance and resonance decay, and compares results with ALICE data.

## Key findings

- $D$-measure strongly depends on pseudorapidity acceptance in HIJING and UrQMD.
- Resonance decay and $p_T^{min}$ thresholds influence fluctuation measures.
- Model results differ from extrapolated functions at higher $
abla heta$ and lower energies.

## Abstract

We study the net-charge fluctuations, $D$-measure variable, in high energy heavy-ion collisions in heavy-ion jet interaction generator (HIJING), ultrarelativistic quantum molecular dynamics (UrQMD) and hadron resonance gas (HRG) models for various center-of-mass energies (\sqsn). The effect of kinematic acceptance and resonance decay, in the pseudorapidity acceptance interval ($\Delta\eta$) and lower transverse momentum ($p_{T}^{min}$) threshold, on fluctuation measures are discussed. A strong dependence of $D$ with the $\Delta\eta$ in HIJING and UrQMD models is observed as opposed to results obtained from the HRG model. The dissipation of fluctuation signal is estimated by fitting the $D$-measure as a function of the $\Delta\eta$. An extrapolated function for higher $\Delta\eta$ values at lower \sqsn is different from the results obtained from models. Particle species dependence of $D$ and the effect of the $p_T^{min}$ selection threshold are discussed in HIJING and HRG models. The comparison of $D$, at midrapidity, of net-charge fluctuations at various \sqsn obtained from the models with the data from the ALICE experiment is discussed. The results from the present work as a function of $\Delta\eta$ and \sqsn will provide a baseline for comparison to experimental measurements.