Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Discovery of a New Companion and Evidence of a Circumprimary Disk:
  Adaptive Optics Imaging of the Young Multiple System VW Cha   Since a majority of young low-mass stars are members of multiple systems, the
study of their stellar and disk configurations is crucial to our understanding
of both star and planet formation processes. Here we present near-infrared
adaptive optics observations of the young multiple star system VW Cha. The
previously known 0.7 arcsec binary is clearly resolved already in our raw J and
K band images. We report the discovery of a new, faint companion to the
secondary, at an apparent separation of only 0.1 arcsec or 16 AU. Our
high-resolution photometric observations also make it possible to measure the
J-K colors of each of the three components individually. We detect an infrared
excess in the primary, consistent with theoretical models of a circumprimary
disk. Analytical and numerical calculations of orbital stability show that VW
Cha may be a stable triple system. Using models for the age and total mass of
the secondary pair, we estimate the orbital period to be 74 years. Thus,
follow-up astrometric observations might yield direct dynamical masses within a
few years, and constrain evolutionary models of low-mass stars. Our results
demonstrate that adaptive optics imaging in conjunction with deconvolution
techniques is a powerful tool for probing close multiple systems.

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The categories of this paper are: funct-an
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
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The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: econ