Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Change in the orbital period of a binary system due to an outburst in a
  windy accretion disc   We consider a new mechanism for the removal of the angular momentum from an
X-ray binary system and the change in its orbital period - the mass loss in the
form of a wind from an accretion disc. Both observations and models predict
powerful winds from discs in X-ray transients. We have obtained an analytical
estimate for the increase in the orbital period of a binary system with a wind
from the disc during an outburst, and quantitative estimates are given for the
systems XTE J1118+480, A0620-00 and GRS 1124-68. Resulting rate of period grow
is of order of the observed rates of secular decrease in the period. We also
compare the predicted rate of change in the period of a binary system due to
the flow of matter into the disc and outflow from the second Lagrange point
with the observations. It is concluded that the above mechanisms cannot explain
the observed secular decrease in the period of the three X-ray Novae, and it is
necessary to consider a circumbinary disc that drains the binary's angular
momentum.

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The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th