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arXiv · 2412.04994

Excited cluster states: A new source for proton number fluctuations in the high baryon density regime

Boris Tomasik·Marcus Bleicher
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Abstract

We calculate the contribution of the decay products of excited nuclear cluster states to the event-by-event fluctuations of protons in the energy range from $\sqrt{s_{NN}}=2-5$~GeV within the statistical model. We find that the inclusion of the excited nuclear clusters yields corrections to all cumulant ratios, ranging from 1\% for ratio of second to first-order cumulant to 100\% for the sixth to second order cumulant towards the lowest inspected energy. As expected the contribution of excited cluster states is most important at low energies $\sqrt{s_{NN}}<3.5$~GeV and becomes negligible at higher collision energies. Especially in light of the expected ultra-high precision data from CBM at FAIR, this new contribution is important to allow for a quantitative comparison with (potentially later available) lattice QCD or effective model results.

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Boris Tomasik, Marcus Bleicher. 2024-12-06. Excited cluster states: A new source for proton number fluctuations in the high baryon density regime. https://arxiv.org/abs/2412.04994

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