Speaker
Description
The speed of sound $c_s$ in strongly interacting matter encodes the stiffness of the nuclear equation of state (EOS). Recent theoretical work has argued that $c_s^2$ can be extracted experimentally from the logarithmic slope between the mean transverse momentum $\langle p_{T} \rangle$ and charged multiplicity $\langle dN/d\eta \rangle$ in ultra-central collisions. In ultra-central collisions, it is conjectured that the effective interaction volume becomes fixed, leading to a sensitivity of the $\langle p_{T} \rangle$ to the EOS that is otherwise diluted by volume variation in more peripheral regimes. The goal is to measure the speed of sound as a function of collision energy for the majority of data taken during the STAR Beam Energy Scan Phase II. We apply this framework initially to ultra-central Au+Au collisions at $\sqrt{s_{\rm NN}}$=200 GeV and determine the slope parameter $ (dln\langle p_{T} \rangle)/dln\langle dN/d\eta \rangle)$ which serves as a potential experimental proxy for $c_s^2$. In addition, we compare our data to previous measurements at higher energy from ALICE and CMS.
