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arXiv · 2108.13814

Pionic depth of the hadron gas after a heavy-ion collision

Guillermo Gómez Fonfría·Felipe J. Llanes-Estrada·Javier Suárez Sucunza·Juan M. Torres-Rincon
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Abstract

The final stage of a relativistic heavy-ion collision is a hadron gas. Final-state interactions therein distort the $p_T$ spectrum of particles coming from the phase transition upon cooling the quark-gluon plasma. Using recent state-of-the-art parametrizations of pion interactions we provide theoretical computations of the pionic depth of the gas: how likely is it that a given pion rescatters in it (we find a high probability around $p_T=0.5$ GeV at midrapidity, corresponding to the formation of the $\rho$ resonance), a comparison of the collision and Bjorken expansion rates, and how many pions make it through without interacting as a function of $p_T$. This is in the range 10-24$\%$ and shown in this plot, the main result of the contribution.

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Guillermo Gómez Fonfría, Felipe J. Llanes-Estrada, Javier Suárez Sucunza, Juan M. Torres-Rincon. 2021-08-31. Pionic depth of the hadron gas after a heavy-ion collision. https://doi.org/10.22323/1.398.0280

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