Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photoproduction of eta-Mesons off 3He   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

3
The categories of this paper are: physics
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs