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arXiv · 2112.02402

Quantifying corrections to the hadron resonance gas with lattice QCD

Rene Bellwied·Szabolcs Borsányi·Zoltán Fodor·Jana N. Guenther·Sándor D. Katz·Paolo Parotto·Attila Pásztor·Dávid Pesznyák·Claudia Ratti·Kálmán K. Szabó
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Abstract

The hadron resonance gas (HRG) model and its extensions are often used to describe the hadronic phase of strongly interacting matter. In our work we use lattice-QCD simulations with temporal extents of $N_\tau=8,10$ and $12$ to quantify corrections to the ideal HRG. Firstly, we determine a number of subleading fugacity expansion coefficients of the QCD free energy via a two-dimensional scan on the imaginary baryon number chemical potential ($\mu_B$) - strangeness chemical potential ($\mu_S$) plane. Using the aforementioned coefficients, we also extrapolate ratios of baryon number and strangeness fluctuations and correlations to finite chemical potentials via a truncated fugacity expansion. Our results extrapolated along the crossover line $T_\mathrm{c}(\mu_B)$ at strangeness neutrality are able to reproduce trends of experimental net-proton fluctuations measured by the STAR Collaboration.

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Rene Bellwied, Szabolcs Borsányi, Zoltán Fodor, Jana N. Guenther, Sándor D. Katz, Paolo Parotto, Attila Pásztor, Dávid Pesznyák, Claudia Ratti, Kálmán K. Szabó. 2021-12-04. Quantifying corrections to the hadron resonance gas with lattice QCD. https://arxiv.org/abs/2112.02402

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