Speed of sound and baryon cumulants in heavy-ion collisions

Abstract

We present a method that may allow an estimate of the value of the speed of sound as well as its logarithmic derivative with respect to the baryon number density in matter created in heavy-ion collisions. To this end, we utilize well-known observables: cumulants of the baryon number distribution. In analyses aimed at uncovering the phase diagram of strongly interacting matter, cumulants gather considerable attention as their qualitative behaviour along the explored range of collision energies is expected to aid in detecting the QCD critical point. We show that the cumulants may also reveal the behavior of the speed of sound in the temperature and baryon chemical potential plane. We demonstrate the applicability of such estimates within two models of nuclear matter, and explore what might be understood from known experimental data.

6 pages, 3 figures; a few minor changes; published version

References in corpus (5)

• Sound velocity bound and neutron stars
• A collision geometry-based 3D initial condition for relativistic heavy-ion collisions
• Fluctuation dynamics near the QCD critical point
• Cumulants of multiple conserved charges and global conservation laws
• Extraction of the sound velocity from rapidity spectra: Evidence for QGP formation at FAIR/RHIC-BES energies

Cited by in corpus (7)

• Reaching percolation and conformal limits in neutron stars
• Causality violation and the speed of sound of hot and dense quark matter in the Nambu--Jona-Lasinio model
• Hydrodynamic attractors for the speed of sound in holographic Bjorken flow
• Speed of sound and liquid-gas phase transition in nuclear matter
• Thermodynamic approach to proton number fluctuations in baryon-rich heavy-ion matter created at moderate collision energies
• Conformality and percolation threshold in neutron stars
• Fluctuations of conserved charges in hydrodynamics and molecular dynamics