2003/06/30 by C. L. Korpa, M. F. M. Lutz · 13 citations
Physics and Astronomy · #Covariant transformation #Isobar #Nuclear matter #Nuclear physics #Nuclear physics research studies #Nucleon #Particle physics #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quantum electrodynamics #Quantum mechanics #Quantum, superfluid, helium dynamics #Resonance (particle physics) #Scattering #nucl-th
paper · pdf · doi:10.1016/j.nuclphysa.2004.06.031
published in Nuclear Physics A 742(3-4), 305-321 (Elsevier BV) · 20 pages, 7 figure, revised manuscript
arxiv created 2004/04/02 · openalex publication_date 2004/07/16 · arxiv updated 2010/12/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We evaluate the in-medium spectral functions for pions, nucleon and isobar resonances in a self consistent and covariant manner. The calculations are based on a recently developed formulation which leads to predictions in terms of the pion-nucleon scattering phase shifts and a set of Migdal parameters describing important short range correlation effects. We do not observe significant softening of pion modes if we insist on reasonable isobar resonance properties but predict a considerable broadening of the N(1440) and N(1520) resonances in nuclear matter. Contrasted results are obtained for the s-wave N(1535) and N(1650) resonances which are affected by a nuclear environment very little. The properties of slowly moving isobar's in nuclear matter are found to depend very sensitively on a soft form factor in the piNN vertex, which is not controlled by the piN scattering data.