Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Study of the $\bm{p+^6}$Li$\bm{\to\eta+^7}$Be reaction 11.3 MeV above
  threshold   The cross section for the reaction $p+^6\text{Li}\to\eta+^7\text{Be}$ was
measured at an excess energy of 11.28 MeV above threshold by detecting the
recoiling $^7$Be nuclei. A dedicated set of focal plane detectors was built for
the magnetic spectrograph Big Karl and was used for identification and four
momentum measurement of the $^7$Be. A differential cross section of
$\frac{d\sigma}{d\Omega}=(0.69\pm{0.20}\text{(stat.)}\pm
0.20\text{(syst.)})\text{nb/sr}$ for the ground state plus the 1/2$^-$ was
measured. The result is compared to model calculations.

4
The categories of this paper are: cond-mat
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics