Phase transition amplification of proton number fluctuations in nuclear collisions from a transport model approach

Abstract

The time evolution of particle number fluctuations in nuclear collisions at intermediate energies ($E_{\mathrm{lab}}=1.23-10A$ GeV) is studied by means of the UrQMD-3.5 transport model. The transport description incorporates baryonic interactions through a density-dependent potential. This allows for an implementation of a first order phase transition including a mechanically unstable region at large baryon density. The scaled variance of the baryon and proton number distributions is calculated in the central cubic spatial volume of the collisions at different times. A significant enhancement of fluctuations associated with the unstable region is observed. This enhancement persists to late times reflecting a memory effect for the fluctuations. The presence of the phase transition has a much smaller influence on the observable event-by-event fluctuations of protons in momentum space.

9 pages, 6 figures

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Cited by in corpus (6)

• The QCD phase diagram and Beam Energy Scan physics: a theory overview
• QCD Equation of State of Dense Nuclear Matter from a Bayesian Analysis of Heavy-Ion Collision Data
• Molecular dynamics analysis of particle number fluctuations in the mixed phase of a first-order phase transition
• Coordinate versus momentum cuts and effects of collective flow on critical fluctuations
• Optimal collision-energy range for realizing macroscopic high-baryon-density matter
• The time evolution of light nuclei cumulants and ratios with a first-order phase transition in the UrQMD transport model