Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic-oscillation Mechanism for Understanding Timing Noise of Pulsar
  Observation   Highly precise pulsar timing is very important for understanding the nature
of a neutron star, and it can even be used to detect gravitational waves.
Unfortunately, the accuracy of the pulsar timing is seriously affected by the
spin-down irregularities of pulsars.

17
The categories of this paper are: q-fin
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg