Photoproduction of eta-Mesons off 3He

TL;DR

This study investigates eta-meson photoproduction off 3He using the MAMI accelerator, revealing strong final state interactions and confirming a narrow resonance structure on the neutron at W ≈ 1.7 GeV.

Contribution

It provides improved measurements of cross sections for eta-meson photoproduction on 3He and quasi-free nucleons, highlighting the role of final state interactions and resonance structures.

Findings

Evidence for dominant final state interaction in eta-photoproduction

Confirmation of a narrow bump-like structure at W ≈ 1.7 GeV on the neutron

Improved statistical quality of total cross section measurements

Abstract

Photoproduction of eta-mesons off 3He has been studied at the MAMI accelerator using the Crystal Ball/TAPS detector setup. The total cross section for the coherent eta-photoproduction was measured with improved statistical quality. Both, the total and differential cross sections show evidence for dominant final state interaction. Additionally, the photoproduction of eta- mesons off quasi-free protons and neutrons was studied. The preliminary cross section on the neutron confirms the narrow bump-like structure at W \simeq 1.7 GeV, which was already seen in different experiments on the deuterium target