Neutrino excitation of nucleon resonances in a relativistic quark model

Abstract

Neutrino excitation of nucleon resonances is considered in a quark model based on a relativistic wave equation, whose normalizable solutions are used to deseribe hadronic states. It is found, on the basis of the consistent calculation of current matrix elements, that the structure of hadrons cannot be completely described by the inner motion of pointlike quarks. Calculated cross-sections for the excitation of the P33(1236) resonance are compared with experimental data. The model predicts that, for all the three resonance peaks considered here, the partial cross-section σL dominates both σR and σS on the average,i.e. taking into account all the resonances building any of these peaks.