Extracting the speed of sound of QCD from transverse momentum fluctuations

Mubarak Alqahtani, Tribhuban Parida, Jean-Yves Ollitrault

We extract the speed of sound ($c_s$) in the quark-gluon plasma from ATLAS data on the probability distribution of the transverse momentum per particle, $[p_T]$, in ultra-central P…