# Multiplicity fluctuations in Ar+Sc collisions at the CERN SPS from NA61/SHINE

## TL;DR

This paper investigates multiplicity fluctuations in Ar+Sc collisions at various energies using the NA61/SHINE detector, providing new insights into particle production variability and comparing results with other collision systems and simulations.

## Contribution

It presents the first detailed analysis of multiplicity fluctuations in Ar+Sc collisions across multiple energies, using novel centrality selection and fluctuation measures.

## Key findings

- Scaled variance {} and measure {} were obtained for different hadron charges.
- Results show differences between Ar+Sc, p+p, and Pb+Pb collision data.
- Comparisons with EPOS 1.99 simulations highlight model-data agreements and discrepancies.

## Abstract

Multiplicity fluctuations were investigated in Ar+Sc collisions at 13A, 19A, 30A, 40A, 75A, 150A GeV/c using the NA61/SHINE detector at the SPS. Centrality selection is based on the nucleon-spectator energy in the forward hemisphere as measured by the Projectile spectator detector. Preliminary results on the scaled variance {\omega} and the strongly intensive measure {\Omega} were obtained for the multiplicity distribution of all, negatively and positively charged hadrons. Results are discussed and compared with p+p results and Pb+Pb data of NA49 and EPOS 1.99 simulations.