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arXiv · 2208.04806

Thermal fluctuations on the freeze-out surface of heavy-ion collisions and their impact on particle correlations

Adrian Skasberg Aasen·Stefan Floerchinger·Giuliano Giacalone·Deniz Guenduez
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Abstract

Particle momentum distributions originating from a quark-gluon plasma as produced in high-energy nuclear collisions can be influenced by thermal fluctuations in fluid dynamic fields. We study this effect by generalizing the commonly used kinetic freeze-out prescription by allowing for small fluctuations around an average in fluid velocity, chemical potentials and temperature. This leads to the appearance of specific two-body momentum correlations. Combining a blast-wave parametrization of the kinetic freeze-out surface with the thermal correlation functions of an ideal resonance gas, we perform an exploratory study of angular net-charge correlations induced by thermal fluctuations around vanishing chemical potential. We note a diffusion of the near-side peak around $\Delta y=\Delta\phi=0$ induced by variances of different chemical potentials, which could be investigated experimentally.

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Adrian Skasberg Aasen, Stefan Floerchinger, Giuliano Giacalone, Deniz Guenduez. 2022-08-09. Thermal fluctuations on the freeze-out surface of heavy-ion collisions and their impact on particle correlations. https://doi.org/10.1103/physrevc.108.014904

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