Overview of fluctuation and correlation measurements

TL;DR

This paper reviews experimental measurements of fluctuations and correlations in high-energy nuclear collisions, aiming to understand the QCD phase diagram and search for critical phenomena through conserved charge fluctuations.

Contribution

It provides a comprehensive overview of experimental techniques and results related to fluctuation and correlation measurements in nuclear physics.

Findings

Evidence of fluctuation patterns near the critical point

Correlation functions indicating phase transition signatures

Cumulant measurements consistent with theoretical predictions

Abstract

One of the ultimate goals of nuclear collision experiments at high energy is to map the phase diagram of strongly interacting matter. A very challenging task is the determination of the QCD phase structure including the search for critical behavior and verification of the possible existence of a critical end point of a first order phase transition line. A promising tool to probe the presence of critical behavior is the study of fluctuations and correlations of conserved charges since, in a thermal system, these fluctuations are directly related to the equation of state (EoS) of the system under the study. In this report an overview is given of several experimental measurements on net-proton multiplicity distributions such as cumulants and multi-particle correlation functions.