Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The information content of a new observable: the case of the nuclear
  neutron skin
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
3
The categories of this paper are: physics
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph