Speaker
Description
The ratios of the cumulants of identified net-partile multiplicity distributions have been suggested to be sensitive to the onset of QCD phase transition and to the additional fluctuations expected from the close proximity to the critical point [1,2,3].
We report the first measurements of $6^{th}$ order cumulants of net-charge distributions, up to $3^{rd}$ order cumulants of net-$\Lambda$ distributions, and off-diagonal cumulants of net-charge, net-proton, and net-kaon distributions for Au+Au collisions at BES energies using particle species dependent efficiencies. Net-proton cumulants up to $4^{th}$ order have been obtained with unfolding to correct for non-binomial detector effects as well as a new method for volume fluctuation corrections [4]. We show the first measurement of cumulant ratios ($C_{2}/C_{1}$, $C_{3}/C_{2}$) of net-$\Lambda$, which are each subject to strangeness and baryon number conservation. We extract the chemical freeze-out parameters ($\mu_{B}$, $T$) from these measurements under the assumption that the experimental multiplicity cumulant ratios are equivalent to the ratios of susceptibilities from the lattice.
[1] M.A.Stephanov, Phys. Rev. Lett. 102, 032301 (2009).
[2] B. Friman, F. Karsch, K. Redlich, V. Skokov, Eur. Phys. J. C 71, 1694 (2011).
[3] A. Majumder and B. Muller, Phys. Rev. C 74, 054901 (2006).
[4] P. Braun-Munzinger, A. Rustamov, and J. Stachel, Nucl. Phys., A960:114130, 2017.
| Content type | Experiment |
|---|---|
| Collaboration | STAR |
| Centralised submission by Collaboration | Presenter name already specified |
