$N-N$, $P_{T}-N$ and $P_{T}-P_{T}$ fluctuations in nucleus-nucleus collisions at the NA61/SHINE experiment

TL;DR

This paper reports on measurements of fluctuations in nucleus-nucleus collisions at the NA61/SHINE experiment, aiming to identify signs of the critical point of strongly interacting matter through pseudorapidity-dependent fluctuation analysis.

Contribution

It presents the first preliminary results on transverse momentum and multiplicity fluctuations in Be+Be collisions, exploring their pseudorapidity dependence and potential sensitivity to the critical point.

Findings

Fluctuations evolve from Poissonian-like at small pseudorapidity intervals.

Non-trivial fluctuation effects are observed with increasing acceptance.

Results are compared with EPOS model predictions.

Abstract

The NA61/SHINE experiment aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. For these goals a scan of the two dimensional phase diagram ($T-\mu_{B}$) is being performed at the SPS by measurements of hadron production in proton-proton, proton-nucleus and nucleus-nucleus interactions as a function of collision energy. This paper presents preliminary results from Be+Be collisions on pseudorapidity dependences of transverse momentum and multiplicity fluctuations expressed in terms of strongly intensive quantities. It is shown that non-trivial effects evolve from the Poissonian-like fluctuations for small pseudorapidity intervals with expansion of the acceptance. These fluctuations are supposed to be sensitive to the existence of the critical point. The results will be compared to the predictions from the EPOS model.