1995/11/01 by Nimai C. Mukhopadhyay, J. -F. Zhang, Mukhopadhyay, Nimai C. +4
Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear Theory (nucl-th) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph #nucl-th
paper · pdf · doi:10.48550/arxiv.nucl-th/9511001
1 fig. in ps.. It is an invited talk in Baryon'95, Santa Fe, Oct. 1995
arxiv created 1995/11/01 · openalex publication_date 1995/11/01 · arxiv updated 2016/09/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
From the new Mainz data of eta photoproduction off protons\citeref1 and deuterons\citeref2, we can extract, via the effective Lagrangian approach (ELA)\citeref3, the electrostrong parameters ξp and ξn for the N^*(1535) excitation. These parameters are, in units of 10-4 MeV-1, (2.20± 0.15) and (-1.86± 0.20) respectively. They yield the ratio of the helicity amplitudes for the excitation of N^*(1535) by photons off neutrons and protons to be An1/2/Ap1/2=-0.84± 0.15, a quantity of fundamental importance in the baryon structure. Best estimates in the quark model are close to this ratio.