TY - JOUR
T1 - Quartic cumulant of baryon number in the presence of a QCD critical point
AU - Mroczek, D.
AU - Nava Acuna, A. R.
AU - Noronha-Hostler, J.
AU - Parotto, P.
AU - Ratti, C.
AU - Stephanov, M. A.
N1 - Funding Information:
This material is based upon work supported by the National Science Foundation under Grant No. PHY-1654219 and by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, within the framework of the Beam Energy Scan Topical (BEST) Collaboration and Grants No. DE-SC0020633 and No. DE-FG02-01ER41195. We also acknowledge the support from the Center of Advanced Computing and Data Systems at the University of Houston. J.N.-H. acknowledges support from the Alfred P Sloan Foundation. P.P. acknowledges support by the DFG Grant No. SFB/TR55. D.M. was supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE - 1746047.
Publisher Copyright:
© 2021 American Physical Society.
PY - 2021/3
Y1 - 2021/3
N2 - In the context of the ongoing search for the QCD critical point at the Relativistic Heavy-Ion Collider, we study the equation of state near the critical point in the temperature and baryon chemical potential plane. We use the parametric representation introduced in earlier literature, which maps the universal three-dimensional Ising equation of state onto the QCD phase diagram using several non-universal parameters. We focus on the quartic cumulant of the baryon number, or baryon number susceptibility χ4B, which can be accessed experimentally via net-proton fluctuation kurtosis measurements. It was originally predicted, through universality arguments based on the leading singular contribution, that χ4B and net-proton kurtosis should show a specific nonmonotonic behavior due to the critical point. In particular, when following the freeze-out curve on the phase diagram by decreasing beam energy, the kurtosis is expected to dip, and then peak, when the beam energy scan passes close to the critical point. We study the effects of the nonuniversal and thus far unknown parameters of the Ising-to-QCD mapping on the behavior of χ4B. We find that, while the peak remains a solid feature, the presence of the critical point does not necessarily cause a dip in χ4B on the freeze-out line below the transition temperature. The critical point contribution to the dip appears only for a narrow set of mapping parameters, when subleading singular terms are sufficiently suppressed.
AB - In the context of the ongoing search for the QCD critical point at the Relativistic Heavy-Ion Collider, we study the equation of state near the critical point in the temperature and baryon chemical potential plane. We use the parametric representation introduced in earlier literature, which maps the universal three-dimensional Ising equation of state onto the QCD phase diagram using several non-universal parameters. We focus on the quartic cumulant of the baryon number, or baryon number susceptibility χ4B, which can be accessed experimentally via net-proton fluctuation kurtosis measurements. It was originally predicted, through universality arguments based on the leading singular contribution, that χ4B and net-proton kurtosis should show a specific nonmonotonic behavior due to the critical point. In particular, when following the freeze-out curve on the phase diagram by decreasing beam energy, the kurtosis is expected to dip, and then peak, when the beam energy scan passes close to the critical point. We study the effects of the nonuniversal and thus far unknown parameters of the Ising-to-QCD mapping on the behavior of χ4B. We find that, while the peak remains a solid feature, the presence of the critical point does not necessarily cause a dip in χ4B on the freeze-out line below the transition temperature. The critical point contribution to the dip appears only for a narrow set of mapping parameters, when subleading singular terms are sufficiently suppressed.
UR - http://www.scopus.com/inward/record.url?scp=85102931819&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85102931819&partnerID=8YFLogxK
U2 - 10.1103/PhysRevC.103.034901
DO - 10.1103/PhysRevC.103.034901
M3 - Article
AN - SCOPUS:85102931819
SN - 2469-9985
VL - 103
JO - Physical Review C
JF - Physical Review C
IS - 3
M1 - 034901
ER -