Speaker
Mr
Sheng-Tai Li
(Central China Normal University)
Description
The chiral phase transition temperature $T_{c}$ is a fundamental quantity of QCD. To determine this quantity, we have performed simulations of (2 + 1)-flavor QCD using the Highly Improved Staggered Quarks (HISQ) action on $N_{\tau}=6, 8, 12$ lattices and aspect ratios $N_{\sigma}/N_{\tau}$ ranging from 4 to 7.
In our simulations, we fix the strange quark mass value to its physical value $m_{s}^{\rm{phy}}$, and the values of two degenerate light quark masses $m_{l}$ are varied from $m_{s}^{\rm{phy}}/160$ to $m_{s}^{\rm{phy}}/20$ which correspond to a Goldstone pion mass $m_{\pi}$ ranging from 55 MeV to 160 MeV in the continuum limit.
By investigating the light quark mass dependence and volume dependence of various chiral observables, e.g. chiral susceptibilities and Binder cumulants, we didn't find any evidence for a first order phase transition in our current quark mass window.
By looking at the crossing point of $\chi_{\sigma}/\chi_{\pi}=m_{l}\chi_{tot}/\left\langle \bar{\psi} \psi\right\rangle_{l}$ which is the ratio of light quark mass times chiral susceptibilities and chiral condensates as a function of $T$ and $m_{l}$, we are able to extract the value of $T_{c}$ in the chiral & continuum limit without referring to critical exponents of a particular universality class. The uncertainty in the determination of $T_{c}$ is also discussed.
Primary author
Mr
Sheng-Tai Li
(Central China Normal University)
Co-authors
Dr
Anirban Lahiri
(Bielefeld University)
Prof.
Frithjof Karsch
(Brookhaven National Laboratory)
Prof.
Heng-Tong Ding
(Central China Normal University)
Prof.
Olaf Kaczmarek
(Bielefeld University)
Prof.
Peter Petreczky
(BNL)
Dr
Prasad Hegde
(Indian Institute of Science, INDIA)