Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of a Tight Brown Dwarf Companion to the Low Mass Star LHS
  2397a   Using the adaptive optics system, Hokupa'a, at Gemini-North, we have directly
imaged a companion around the UKIRT faint standard M8 star, LHS 2397a (FS 129)
at a separation of 2.96 AU. Near-Infrared photometry of the companion has shown
it to be an L7.5 brown dwarf and confirmed the spectral type of the primary to
be M8. We also derive a substellar mass of the companion of 0.068 Msun,
although masses in the range (0.061-0.069) are possible, and the primary mass
as 0.090 Msun (0.089-0.094). Reanalysis of archival imaging from HST has
confirmed the secondary as a common proper motion object. This binary
represents the first clear example of a brown dwarf companion within 4 AU of a
low mass star and should be one of the first late L dwarfs to have a dynamical
mass. As part of a larger survey of M8-L0 stars, this object may indicate that
there is no ``brown dwarf desert'' around low mass primaries.

18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int