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arXiv · 1711.09863

van der Waals Interactions and Hadron Resonance Gas: Role of resonance widths modeling on conserved charges fluctuations

Volodymyr Vovchenko·Paolo Alba·Mark I. Gorenstein·Horst Stoecker
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Abstract

The quantum van der Waals (QvdW) extension of the ideal hadron resonance gas (HRG) model which includes the attractive and repulsive interactions between baryons -- the QvdW-HRG model -- is applied to study the behavior of the baryon number related susceptibilities in the crossover temperature region. Inclusion of the QvdW interactions leads to a qualitatively different behavior of susceptibilities, in many cases resembling lattice QCD simulations. It is shown that for some observables, in particular for $χ_{11}^{BQ} / χ_2^B$, effects of the QvdW interactions essentially cancel out. It is found that the inclusion of the finite resonance widths leads to an improved description of $χ_2^B$, but it also leads to a worse description of $χ_{11}^{BQ} / χ_2^B$, as compared to the lattice data. On the other hand, inclusion of the extra, unconfirmed baryons into the hadron list leads to a simultaneous improvement in the description of both observables.

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Volodymyr Vovchenko, Paolo Alba, Mark I. Gorenstein, Horst Stoecker. 2017-11-27. van der Waals Interactions and Hadron Resonance Gas: Role of resonance widths modeling on conserved charges fluctuations. https://doi.org/10.1051/epjconf%2F201817114006

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