https://doi.org/10.1051/epjconf/202024102007
Quark model calculations of transition form factors at high photon virtualities
Laboratório de Física Teórica e Computacional – LFTC, Universidade Cruzeiro do Sul/Universidade Cidade de São Paulo, 01506-000, São Paulo, SP, Brazil
Published online: 22 September 2020
We present calculations of γ*N → N* transition form factors, where N is the nucleon and N* is a nucleon resonance, based on a covariant quark model. Our main focus is at high photon virtualities (large Q2) where the valence quark degrees of freedom dominate the contributions to the transition form factors and helicity amplitudes. In that regime, the quark model estimates can be compared with the available data, particularly with the Jefferson Lab data at intermediate and large momentum transfer (Q2 > 2 GeV2). The main focus is on the Δ(1232)3/2+, N(1440)1/2+, N(1535)1/2- and N(1520)3/2- resonances, but estimates for other higher mass resonances are also discussed.
© The Authors, published by EDP Sciences, 2020
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.