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Mass of the rho^0 meson in ultra-relativistic heavy-ion collision

Alejandro Ayala·Jesus Guillermo Contreras·J. Magnin
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Abstract

We study the behavior of the rho vector mass in the context of the almost baryon-free environment of an ultra-relativistic heavy-ion collision. We show that rho scattering within the hadronic phase of the collision leads to a temperature dependent, decrease of its intrinsic mass at rest, compared to the value in vacuum. The main contributions arise from s-channel scattering with pions through the formation of a1 resonances as well as with nucleons through the formation of even parity, spin 3/2 [N(1720)] and 5/2 [Delta(1905)] nucleon resonances. We show that it is possible to achieve a shift in the intrinsic rho^0 mass of order - 40 MeV, when including the contributions of all the relevant mesons and baryons that take part in the scattering, for temperatures between chemical and kinetic freeze-out.

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Alejandro Ayala, Jesus Guillermo Contreras, J. Magnin. 2004-10-15. Mass of the rho^0 meson in ultra-relativistic heavy-ion collision. https://doi.org/10.1016/j.physletb.2004.10.032

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