Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the magnetic accretor GK Persei in outburst   RXTE made 5 X-ray observations of the magnetic accretor GK Per during its
1996 outburst, recording a count rate of ten times the quiescent level. The
351-s spin pulse shows a deep, nearly sinusoidal modulation, in contrast to the
weaker, double-humped profile of quiescence. The spectrum shows absorption
increased by two orders of magnitude over quiescence. We explain these
differences in terms of the changing accretion geometry as the outbursting disc
forces the magnetosphere inwards, and discuss the 5000-s X-ray QPOs seen during
GK Per's outbursts.

23
The categories of this paper are: solv-int
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat