Conveners
Critical Point: (1)
- Nu Xu
Critical Point: (2)
- Daniel Cebra (University of California, Davis)
Higher-order cumulants ($C_n$) of net-baryon distributions are sensitive to the nature of the QCD phase transition. Recent lattice QCD calculations [1] suggest a negative $C_5/C_1$ and $C_6/C_2$ in the crossover regime at small baryon chemical potential ($\mu_B \leq$ 110 MeV). In addition, lattice QCD predicts a special ordering of cumulant ratios for systems of thermalized QGP [2]: $C_3/C_1 >...
It has long been understood that non-monotonic variation of non-Gaussian cumulants of particle multiplicities as a function of decreasing collision energy and, hence, increasing baryon chemical potential $\mu_B$ can yield tell-tale signatures of the presence of a possible critical point in the QCD phase diagram. In this talk, we shall present quantitative estimates for the magnitude and...
The recent measurements of femtoscopic correlations at NA61/SHINE, using small systems, unravel that the shape of the particle emitting source is not Gaussian. The measurements are based on alpha-stable symmetric L\'evy sources, and we discuss the average pair transverse mass dependence of the source parameters. One of the parameters, the L\'evy exponent $\alpha$, is of particularly...
Calculations of baryon number fluctuations up to the sixth order at finite temperature and density in Ref.[1] have been extended to regime of high baryon chemical potentials with 400 MeV $\leq \mu_B\leq 700$ MeV. A peak structure is found for the dependence of the kurtosis of baryon number distributions, i.e., $R^{B}_{42}=\chi^{B}_{4}/\chi^{B}_{2}$, on the collision energy in a range of 3 GeV...
Predictions for the QCD critical point are made using Bayesian inference techniques within the holographic gauge/gravity correspondence. For that, we employ a Einstein-Maxwell-Dilaton (EMD) model capable of reproducing the latest lattice QCD results at zero and finite baryon density, known to predict a high-density critical endpoint. For the first time, we numerically find the posterior...
Subensemble Acceptance Method (SAM) [1,2] is an essential link between measured event-by-event fluctuations and their grand canonical theoretical predictions such as lattice QCD. The method allows quantifying the global conservation law effects in fluctuations. In its basic formulation, SAM requires a sufficiently large system such as created in central nucleus-nucleus collisions and...
In relativistic heavy-ion collisions, the longitudinal fluctuations of the fireball density caused, e.g., by baryon stopping fluctuations result in event-by-event modifications of the proton rapidity density distribution. I will present the multiparticle rapidity correlation functions due to the varying distribution width of the proton rapidity density in central Au+Au collisions at low...
In this talk I discuss the fluctuations of the net-baryon number density in dense hadronic matter. Chiral dynamics is modeled via the parity doublet Lagrangian, and the mean-field approximation is employed to account for chiral criticality. I explain the qualitative properties and systematics of the second-order susceptibility of the net-baryon number density for individual positive- and...
Using a relativistic transport model to describe the evolution of the quantum chromodynamic matter produced in Au+Au collisions at $\sqrt{s_{NN}}=3-200$ GeV, we study the effect of a first-order phase transition in the equation of state of this matter on the yield ratio $N_tN_p/ N_d^2$ ($tp/d^2$) of produced proton ($p$), deuteron ($d$), and triton ($t$). We find that the large density...
Our ability to predict thermodynamic observables and determine the QCD critical point at real values of chemical potentials is severely limited by the infamous sign problem. To address this issue, there are two common approaches: expanding the QCD partition function in a Taylor series with respect to the charge chemical potentials ($\mu_{B,Q,S}$) or analytically continuing from imaginary...
A hot and dense matter exhibiting collective flow behavior with almost no viscous dissipation has been discovered in ultrarelativistic nuclear collisions. To constrain the fundamental degrees of freedom and equation of state of this matter, this talk will present an extraction of its speed of sound using head-on lead-lead collision data collected by the CMS experiment at a center-of-mass...
