Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Derivation of a gyrokinetic model. Existence and uniqueness of specific
  stationary solutions
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph