Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: In Situ Observations of Preferential Pickup Ion Heating at an
  Interplanetary Shock
1
The categories of this paper are: cs
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th