The use of Kolmogorov-Smirnov test in event-by-event analysis

TL;DR

This paper introduces a novel application of the Kolmogorov-Smirnov test for event-by-event analysis in heavy ion collisions, enabling detection of subtle differences between events beyond traditional moment-based methods.

Contribution

It demonstrates the effectiveness of the Kolmogorov-Smirnov test in identifying non-statistical differences in heavy ion collision events, especially for detecting fireball decay mechanisms.

Findings

KS test detects differences not seen by moment analysis

Method sensitive to spinodal fragmentation signatures

Applicable to various event-by-event analyses

Abstract

We propose to use the Kolmogorov-Smirnov test to uncover non-statistical differences between events created in heavy ion collisions within the same centrality class. The advantage of the method over other approaches which are currently in use, is that it is sensitive to any difference between the events and is not restricted to simple moments of the distribution of hadrons. The particular application examined here is the identification of the fireball decay due to spinodal fragmentation and/or sudden rise of the bulk viscosity.