Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Nature of Stars with Planets   We consider the metallicities and kinematics of nearby stars known to have
planetary-mass companions in the general context of the overall properties of
the local Galactic Disk. We have used Stromgren photometry to determine
abundances for both the extrasolar-planet host stars and for a volume-limited
sample of 486 F, G and K stars selected from the Hipparcos catalogue. The
latter data show that the Sun lies near the modal abundance of the disk, with
over 45% of local stars having super-solar metallicities. Twenty of the latter
stars (4.1%) are known to have planetary-mass companions. Using that ratio to
scale data for the complete sample of planetary host stars, we find that the
fraction of stars with extrasolar planets rises sharply with increasing
abundance, confirming previous results. However, the frequency remains at the
3-4% level for stars within 0.15 dex of solar abundance, and falls to ~1% only
for stars with abundances less than half solar. Given the present observational
constraints, both in velocity precision and in the available time baseline,
these numbers represent a lower limit to the frequency of extrasolar planetary
systems. A comparison between the kinematics of the planetary host stars and a
representative sample of disk stars suggests that the former have an average
age which is ~60% of the latter.

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The categories of this paper are: cs
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The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: q-alg
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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
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The categories of this paper are: adap-org