Weak $\eta$ production off the nucleon

TL;DR

This paper investigates weak eta-meson production off nucleons induced by (anti)neutrinos at energies relevant for neutrino experiments, considering resonance excitations and form factor constraints.

Contribution

It provides a detailed theoretical model including Born diagrams and resonance contributions, with form factors constrained by experimental data and PCAC assumptions.

Findings

Calculated cross sections for eta production at low and intermediate energies.

Inclusion of N* resonances enhances the understanding of production mechanisms.

Provides form factor parametrizations useful for neutrino experiment analyses.

Abstract

The weak $\eta$-meson production off the nucleon induced by (anti)neutrinos is studied at low and intermediate energies, the range of interest for several ongoing and future neutrino experiments. We consider Born diagrams and the excitation of $N^\ast (1535)S_{11}$ and $N^\ast(1650)S_{11}$ resonances. The vector part of the N-$S_{11}$ transition form factors has been obtained from the MAID helicity amplitudes while the poorly known axial part is constrained with the help of the partial conservation of the axial current (PCAC) and assuming the pion-pole dominance of the pseudoscalar form factor.