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In-Medium Modifications of Hadron Masses and Chemical Freeze-Out in Ultra-Relativistic Heavy-Ion Collisions

W. Florkowski·W. Broniowski
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Abstract

We confront the hypothesis of chemical freeze-out in ultra-relativistic heavy-ion collisions with the hypothesis of large modifications of hadron masses in nuclear medium. We find that the thermal-model predictions for the ratios of particle multiplicities are sensitive to the values of in-medium hadronic masses. In particular, the $π^+/p$ ratio decreases by 35% when the masses of all hadrons (except for pseudo-Goldstone bosons) are scaled down by 30%.

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W. Florkowski, W. Broniowski. 1999-10-06. In-Medium Modifications of Hadron Masses and Chemical Freeze-Out in Ultra-Relativistic Heavy-Ion Collisions. https://doi.org/10.1016/s0370-2693(00)00205-7

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