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arXiv · 1808.03102

The thermal proton yield anomaly in Pb-Pb collisions at the LHC and its resolution

Anton Andronic·Peter Braun-Munzinger·Bengt Friman·Pok Man Lo·Krzysztof Redlich·Johanna Stachel
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Abstract

We propose a resolution of the discrepancy between the proton yield predicted by the statistical hadronization approach and data on hadron production in ultra-relativistic nuclear collisions at the LHC. Applying the S-matrix formulation of statistical mechanics to include pion-nucleon interactions, we reexamine their contribution to the proton yield, taking resonance widths and the presence of nonresonant correlations into account. The effect of multi-pion-nucleon interactions is estimated using lattice QCD results on the baryon-charge susceptibility. We show that a consistent implementation of these features in the statistical hadronization model, leads to a reduction of the predicted proton yield, which then quantitatively matches data of the ALICE collaboration for Pb-Pb collisions at the LHC.

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Anton Andronic, Peter Braun-Munzinger, Bengt Friman, Pok Man Lo, Krzysztof Redlich, Johanna Stachel. 2019-01-27. The thermal proton yield anomaly in Pb-Pb collisions at the LHC and its resolution. https://doi.org/10.1016/j.physletb.2019.03.052

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