Freeze-out by bulk viscosity driven instabilities

Giorgio Torrieri; Boris Tomášik; Igor Mishustin

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arXiv · 0803.4070

Freeze-out by bulk viscosity driven instabilities

Giorgio Torrieri·Boris Tomášik·Igor Mishustin

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Abstract

We describe a new scenario (first introduced in [G. Torrieri, B. Tomášik and I. Mishustin, Phys. Rev. C \textbf{77}, 034903 (2008)]) for freezeout in heavy ion collisions that could solve the lingering problems associated with the so-called HBT puzzle. We argue that bulk viscosity increases as $T$ approaches $T_c$. The fluid {then} becomes unstable against small perturbations, and fragments into clusters of a size much smaller than the total size of the system. These clusters maintain the pre-existing outward-going flow, as a spray of droplets, but develop no flow of their own, and hadronize by evaporation. We show that this scenario can explain HBT data and suggest how it can be experimentally tested.

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Giorgio Torrieri, Boris Tomášik, Igor Mishustin. 2008-06-03. Freeze-out by bulk viscosity driven instabilities. https://arxiv.org/abs/0803.4070

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