Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Runaway Binary LP 400-22 is Leaving the Galaxy   We present optical spectroscopy, astrometry, radio, and X-ray observations of
the runaway binary LP 400-22. We refine the orbital parameters of the system
based on our new radial velocity observations. Our parallax data indicate that
LP 400-22 is significantly more distant (3 sigma lower limit of 840 pc) than
initially predicted. LP 400-22 has a tangential velocity in excess of 830 km/s;
it is unbound to the Galaxy. Our radio and X-ray observations fail to detect a
recycled millisecond pulsar companion, indicating that LP 400-22 is a double
white dwarf system. This essentially rules out a supernova runaway ejection
mechanism. Based on its orbit, a Galactic center origin is also unlikely.
However, its orbit intersects the locations of several globular clusters;
dynamical interactions between LP 400-22 and other binary stars or a central
black hole in a dense cluster could explain the origin of this unusual binary.

31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess