2010/08/31 by G. Ramalho, K. Tsushima
Physics and Astronomy · #Baryon #Hadron #Nuclear physics research studies #Particle physics #Particle physics theoretical and experimental studies #Physics #Pion #Quantum Chromodynamics and Particle Interactions #Quark model #Quarkonium #hep-ex #hep-lat #hep-ph #nucl-ex #nucl-th
paper · pdf · doi:10.1103/physrevd.82.073007
published as Phys.Rev.D82:073007,2010 · To appear in Phys. Rev. D. Version with small modifications. 14 pages, 6 figures and 3 tables
arxiv created 2010/09/08 · openalex publication_date 2010/10/13 · arxiv updated 2014/11/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
A covariant spectator constituent quark model is applied to study the \ensuremathγN\ensuremath→\ensuremathΔ(1600) transition. Two processes are important in the transition: a photon couples to the individual quarks of the \ensuremathΔ(1600) core (quark core), and a photon couples to the intermediate pion-baryon states (pion cloud). While the quark core contributions are estimated assuming \ensuremathΔ(1600) as the first radial excitation of \ensuremathΔ(1232), the pion cloud contributions are estimated based on an analogy with the \ensuremathγN\ensuremath→\ensuremathΔ(1232) transition. To estimate the pion cloud contributions in the \ensuremathγN\ensuremath→\ensuremathΔ(1600) transition, we include the relevant intermediate states, \ensuremathπN, \ensuremathπ\ensuremathΔ, \ensuremathπN(1440) and \ensuremathπ\ensuremathΔ(1600). Dependence on the four-momentum transfer squared, Q2, is predicted for the magnetic dipole transition form factor, GM*(Q2), as well as the helicity amplitudes, A1/2(Q2) and A3/2(Q2). The results at Q2=0 are compared with the existing data.