Measurements of Kaon Femtoscopy in Au+Au Collisions at $\sqrt{s_{NN}}$ = 3.0-4.5 GeV by the STAR Experiment

TL;DR

This paper reports the first systematic measurements of kaon-kaon correlation functions in high baryon density Au+Au collisions at STAR, revealing source size behaviors that differ from pions and are qualitatively modeled by UrQMD.

Contribution

It provides new systematic measurements of kaon femtoscopy in a high baryon density regime, expanding understanding of particle correlations in this energy range.

Findings

Source sizes show no clear energy dependence.

Kaon source size transverse mass dependence differs from pions.

UrQMD model qualitatively reproduces the measurements.

Abstract

In these proceedings, we present the measurements of charged $K^{+} - K^{+}$ and neutral $K_{s}^{0} - K_{s}^{0}$ correlation functions from Au+Au fixed-target collisions at $\sqrt{s_{NN}}$ = 3.0, 3.2, 3.5, 3.9 and 4.5 GeV at STAR. This is the first such systematic measurement of correlation functions involving strangeness in the high baryon density region. The source size values do not exhibit a clear energy dependence, and the transverse mass dependence of source size for kaons does not align with the trend observed for pions. Parameters extracted from UrQMD transport model calculations qualitatively capture the measured values.