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arXiv · 2107.10011

Second order cumulants of conserved charge fluctuations revisited I. Vanishing chemical potentials

D. Bollweg·J. Goswami·O. Kaczmarek·F. Karsch·Swagato Mukherjee·P. Petreczky·C. Schmidt·P. Scior
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Abstract

We update lattice QCD results for second order cumulants of conserved charge fluctuations and correlations at non-zero temperature and vanishing values of the conserved charge chemical potentials. We compare these results to hadron resonance gas calculations with and without excluded volume terms as well as S-matrix results in the hadronic phase of QCD, and comment on their current limitations. We, furthermore, use these results to characterize thermal conditions in the vicinity of the pseudo-critical line of the chiral transition in QCD. We argue that the ratio of strange to baryon chemical potentials is a robust observable that, on the one hand, deviates only little from hadron resonance gas results, but, on the other hand, is very sensitive to the spectrum of strange baryon resonances.

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D. Bollweg, J. Goswami, O. Kaczmarek, F. Karsch, Swagato Mukherjee, P. Petreczky, C. Schmidt, P. Scior. 2021-07-21. Second order cumulants of conserved charge fluctuations revisited I. Vanishing chemical potentials. https://doi.org/10.1103/physrevd.104.074512

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