Higher order cumulants of net baryon-number distributions at non-zero μ

Journal Article · Thu Dec 10 00:00:00 EST 2020 · Nuclear Physics. A

DOI:https://doi.org/10.1016/j.nuclphysa.2020.121835· OSTI ID:1763345

Bollweg, D.  ^[1]; Karsch, F. ^[1]; Mukherjee, S. ^[2]; Schmidt, C. ^[1]

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1. Univ. Bielefeld (Germany)
2. Brookhaven National Lab. (BNL), Upton, NY (United States)

Using recent results on higher order cumulants of conserved charge fluctuations from lattice QCD, we construct mean, variance, skewness, kurtosis, hyper-skewness and hyper-kurtosis of net-baryon number distributions for small baryon chemical potentials μ_B. For the strangeness neutral case (μ_S = 0) at fixed ratio of electric charge to baryon number density ( $\frac{n_Q}{n_B}=0.4$), which is appropriate for a comparison with heavy ion collisions, we present results for κ_Bσ²_B, S_Bσ³_B/M_B, κ^H_Bσ⁴_B and S^H_Bσ⁵_B/M_B on the crossover line for the chiral transition, T_pc(μ_B). Furthermore, continuum extrapolations for this pseudo-critical transition line have recently been reported by HotQCD up to baryon chemical potentials μ_B ≃ 300 MeV [A. Bazavov, et al., Chiral crossover in QCD at zero and non-zero chemical potentials, Phys. Lett. B 795 (2019) 15–21. arXiv:1812.08235.]. These cumulant ratios are of direct relevance for comparisons with corresponding ratios measured by STAR in the BES-I and II runs at beam energies $\sqrt{s_{\mathrm{NN}}}\ge 20\text{GeV}$. In particular, we point out that recent high statistics results on skewness and kurtosis of net-baryon number distributions obtained by STAR at $\sqrt{s_{\mathrm{NN}}}=54.4\text{GeV}$ put strong constraints on freeze-out parameters and are consistent with predictions from thermal QCD.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP); German Research Foundation (DFG); GBBF
• Grant/Contract Number: SC0012704; 315477589; 05P2018
• OSTI ID: 1763345
• Alternate ID(s): OSTI ID: 1760944
• Report Number(s): BNL-220897-2021-JAAM; TRN: US2205955
• Journal Information: Nuclear Physics. A, Vol. 1005; ISSN 0375-9474
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
Lattice QCD
freeze-out
fluctuations
cumulants