Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Absolute frequency measurement of the 7s$^2$ $^1$S$_0$ $-$ 7s7p
  $^{1}$P$_1$ transition in $^{225}$Ra
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph