Delta(1232) and Nucleon Spectral Functions in Hot Hadronic Matter

Abstract

Modifications of Delta(1232) and nucleon spectral functions at finite temperature and baryon density are evaluated in terms of resonant scattering off thermal pions, as well as a renormalization of the vacuum Delta-width including vertex corrections. The interactions are based on effective Lagrangians of pions and baryon resonances, with underlying parameters (coupling constants and form factors) determined by the elastic pi N scattering phase shift in the isobar channel, and by empirical decay branchings of excited resonances. Pion modifications are included via interactions in a pion gas, as well as standard Delta- and nucleon-hole excitations in nuclear matter. In hot hadronic matter, under conditions resembling thermal freezeout at the Relativistic Heavy-Ion Collider (RHIC), the Delta exhibits a significant broadening of ~65 MeV together with a slight upward peak shift of 5-10 MeV, in qualitative agreement with preliminary data from the STAR collaboration.

7 pages, 5 figures v2: Version accepted for publication in Phys. Lett. B, replaced one figure, added and updated references

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Cited by in corpus (14)

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• Critical Density and Impact of $\Delta (1232)$ Resonance Formation in Neutron Stars
• Strange mesons in nuclear matter at finite temperature
• Isospin-dependent pion in-medium effects on charged pion ratio in heavy ion collisions
• Delta mass shift as a thermometer of kinetic decoupling in Au+Au reactions at 1.23 AGeV
• Photoabsorption off nuclei with self consistent vertex corrections
• Covariant and self consistent vertex corrections for pions and isobars in nuclear matter
• ${\Xi }^0(1530)$ Production in Heavy-Ion Collisions \linebreak and its Implications for $\Delta t_{therm-chem}$
• Dileptons and Medium Effects in Heavy-Ion Collisions
• $\Delta$ self-energy at finite temperature and density and the $\pi N$ cross-section
• Relativistic spectral function of nucleon in hot nuclear matter
• A unified approach to hadron phenomenology at zero and finite temperatures in a hard-wall AdS/QCD model
• Correlated pion-proton pair emission off hot and dense QCD matter
• Medium effects on charged pion ratio in heavy ion collisions