sPHENIX is a new detector at RHIC.

["Huang, Jin" <jhuang AT bnl.gov>]

FYI

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From: Frank Geurts <geurts AT rice.edu>
Sent: Saturday, February 1, 2025 4:00:51 PM
To: Huang, Jin <jhuang AT bnl.gov>; Connors, Megan <mconnors AT bnl.gov>; Akiba, Yasuyuki <akiba AT bnl.gov>; Deshpande, Abhay <abhay AT bnl.gov>
Cc: Ruan, Lijuan <ruan AT bnl.gov>
Subject: New STAR paper ready for submission: "Precision Measurement of (Net-)proton Number Fluctuations in Au+Au Collisions at RHIC"

Dear Abhay, Jin, Megan, and Akiba-san, 

We are pleased to announce that STAR plans to submit the following paper for publication in one week.

Target journal: Phys. Rev. Lett.

Title: "Precision Measurement of (Net-)proton Number Fluctuations in Au+Au Collisions at RHIC"

Abstract:

We report precision measurements on cumulants (Cn) and factorial cumulants (κn) of (net-)proton number distributions up to fourth-order in Au+Au collisions from phase II of the Beam Energy Scan program at RHIC. (Anti-)protons are selected at midrapidity (|y|< 0.5) within a transverse momentum range of 0.4 < pT < 2.0 GeV/c. The collision energy and centrality dependence of these cumulants are studied over center-of-mass energies √sN N = 7.7 – 27 GeV. Relative to various non-critical-point model calculations and peripheral collision 70-80% data, the net-proton C4/C2 measurement in 0-5% collisions shows a minimum around 19.6 GeV for significance of deviation at∼2 – 5σ. In addition, deviations from non-critical baselines around the same collision energy region are also seen in proton factorial cumulant ratios, especially in κ2/κ1 and κ3/κ1. Dynamical model calculations including a critical point are called for in order to understand these precision measurements.

Best regards,
Frank & Lijuan

________________________________________________________________________
Frank Geurts   (he/him)
Professor of Physics & Astronomy • Rice University, Houston TX
 T.W. Bonner Nucl. Lab.          • Dept. of Physics & Astronomy
 office 713-348-5314             • web http://heavyions.rice.edu
________________________________________________________________________