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

Autor: Oleh Savchuk, Roman V. Poberezhnyuk, Anton Motornenko, Jan Steinheimer, Mark I. Gorenstein, Volodymyr Vovchenko
Rok vydání: 2023
Předmět:
Zdroj: Physical Review
ISSN: 2469-9993
2469-9985
DOI: 10.1103/physrevc.107.024913
Popis: The time evolution of particle number fluctuations in nuclear collisions at intermediate energies ($E_{\rm lab} = 1.23-10A$ 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.
Comment: 9 pages, 6 figures
Databáze: OpenAIRE