2013/07/31 by D. Cabrera, Ralf Rapp, R. Rapp
Physics and Astronomy · #Atomic physics #Hadron #High-Energy Particle Collisions Research #Meson #Momentum (technical analysis) #Nuclear density #Nuclear matter #Nuclear physics #Nuclear physics research studies #Nucleon #Physics #Pion #Propagator #Quantum Chromodynamics and Particle Interactions #Quantum mechanics #Resonance (particle physics) #Scattering #Self-energy #Spectral line #Vertex (graph theory) #hep-ph #nucl-ex #nucl-th
paper · pdf · doi:10.1016/j.physletb.2013.12.056
7 pages, 4 eps figures; v2: includes 3-mom dependence of width and additional discussion
arxiv created 2013/12/11 · openalex publication_date 2014/01/02 · arxiv updated 2015/06/16 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
The width of the ω meson in cold nuclear matter is computed in a hadronic many-body approach, focusing on a detailed treatment of the medium modifications of intermediate πρ states. The π and ρ propagators are dressed by their self-energies in nuclear matter taken from previously constrained many-body calculations. The pion self-energy includes Nh and Δh excitations with short-range correlations, while the ρ self-energy incorporates the same dressing of its 2π cloud with a full 3-momentum dependence and vertex corrections, as well as direct resonance-hole excitations; both contributions were quantitatively fit to total photo-absorption spectra and πN→ρN scattering. Our calculations account for in-medium decays of type ωN→πN(⁎),ππN(Δ), and 2-body absorptions ωNN→NN(⁎),πNN. This causes deviations of the in-medium ω width from a linear behavior in density, with important contributions from spacelike ρ propagators. The ω width from the ρπ cloud may reach up to 200 MeV at normal nuclear matter density, with a moderate 3-momentum dependence. This largely resolves the discrepancy of linear T–ϱ approximations with the values deduced from nuclear photoproduction measurements.