2000/08/31 by M. Post, U. Mosel · 5 citations
Physics and Astronomy · #Amplitude #Baryon #Coupling (piping) #Coupling constant #Excitation #Hadron #Helicity #Isoscalar #Isovector #Meson #Nuclear physics #Nuclear physics research studies #Nucleon #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quantum electrodynamics #Quantum mechanics #Resonance (particle physics) #Vector meson dominance #hep-ph #nucl-th
paper · pdf · doi:10.1016/s0375-9474(00)00583-2
published as Nucl.Phys. A688 (2001) 808-822 · 21 pages, 5 ps figures, misprints corrected, discussion added, improved calculation of gamma N -> omega N, revised version to be published in Nuclear Physics A
arxiv created 2000/11/10 · openalex publication_date 2001/06/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We estimate the resonance coupling strength fRNω and fRNρ from a Vector Meson Dominance (VMD) analysis. The isoscalar and isovector part of the photon coupling are obtained separately from helicity amplitudes. The reliability of this approach is tested by comparing VMD predictions for fRNρ with values obtained from fitting the hadronic decay widths into N ρ. A reasonable agreement is found, but VMD tends to underestimate the coupling constants. In order to confirm consistency with experimental data, we calculate the cross-sections for photon-and pion induced reactions within a \it Breit-Wigner model. Finally, we study how the properties of ω mesons in nuclear matter are affected from the excitation of resonance-hole loops. For an ω at rest, we find a broadening of about 40 MeV, while at higher momenta the effect of resonance excitations is reduced.