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arXiv · 2111.14466

Competition between diffusion and rapid expansion and its impact on critical fluctuations in heavy-ion collisions

Grégoire Pihan·Marcus Bluhm·Masakiyo Kitazawa·Marlene Nahrgang
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Abstract

We study the impact of the competition between the expansion of the medium created in heavy-ion collisions and its diffusive properties on the critical fluctuations of the net-baryon density. As the relaxation time of the fluctuations is connected with the diffusive properties, the latter determine the in- or out-of-equilibrium nature of the net-baryon density fluctuations during the fireball evolution. This may result in important consequences for the phenomenological interpretation of heavy-ion collision data. We study three possible situations that can occur as a result of the competition between diffusion and expansion and discuss the impact of this competition on the integrated second and fourth order cumulants of net-baryon density fluctuations at freeze-out in these situations.

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Grégoire Pihan, Marcus Bluhm, Masakiyo Kitazawa, Marlene Nahrgang. 2021-11-29. Competition between diffusion and rapid expansion and its impact on critical fluctuations in heavy-ion collisions. https://arxiv.org/abs/2111.14466

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