A systematic study of longitudinal and transverse helicity amplidutes in the hypercentral Constituent Quark Model

TL;DR

This paper systematically predicts electromagnetic excitation amplitudes of baryon resonances using a non-relativistic hypercentral Constituent Quark Model, achieving fair agreement with experimental data especially at medium momentum transfer.

Contribution

It provides parameter-free calculations of helicity amplitudes for fourteen resonances, offering a comprehensive analysis within the hypercentral Constituent Quark Model framework.

Findings

Fair description of data at medium Q^2

Parameter-free predictions for 14 resonances

Effective quark model for baryon excitations

Abstract

We report in a systematic way the predictions of the non-relativistic hypercentral Constituent Quark model for the electromagnetic excitations of baryon resonances. The longitudinal and transverse helicity amplitudes are calculated with no free parameters for fourteen resonances, both for proton and neutron. The calculations lead to an overall fair description of data, specially in the medium $Q^2$ range, where quark degrees of freedom are expected to dominate.