2004/09/30 by Hendrik van Hees, H. van Hees, Ralf Rapp +1
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-th
paper · pdf · doi:10.1088/0954-3899/31/4/025
published as J.Phys. G31 (2005) S203-S210 · 7 pages, 4 figures, Talk given at the Hot Quarks 2004 Workshop, Taos,NM, July 18-24 2004, v3: typos corrected
arxiv created 2005/01/26 · openalex publication_date 2005/03/18 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We investigate properties of the Δ(1232) and nucleon spectral functions at finite temperature and baryon density within a hadronic model. The medium modifications of the Δ consist of a renormalization of its pion–nucleon cloud and resonant πΔ scattering. Underlying coupling constants and form factors are determined by the elastic π N scattering phase shift in the isobar channel, as well as empirical partial decay widths of excited baryon resonances. For cold nuclear matter the model provides reasonable agreement with photoabsorption data on nuclei in the Δ-resonance region. In hot hadronic matter typical for late stages of central Au–Au collisions at RHIC we find the Δ-spectral function to be broadened by ∼65 MeV together with a slight upward mass shift of 5–10 MeV, in qualitative agreement with preliminary data from the STAR collaboration.