Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cool White Dwarfs in the Sloan Digital Sky Survey   A reduced proper motion diagram utilizing Sloan Digital Sky Survey (SDSS)
photometry and astrometry and USNO-B plate astrometry is used to separate cool
white dwarf candidates from metal-weak, high-velocity main sequence Population
II stars (subdwarfs) in the SDSS Data Release 2 imaging area. Follow-up
spectroscopy using the Hobby-Eberly Telescope, the MMT, and the McDonald 2.7m
Telescope is used to demonstrate that the white dwarf and subdwarf loci
separate cleanly in the reduced proper motion diagram, and that the
contamination by subdwarfs is small near the cool white dwarf locus. This
enables large statistically complete samples of white dwarfs, particularly the
poorly understood cool white dwarfs, to be created from the SDSS imaging
survey, with important implications for white dwarf luminosity function
studies. SDSS photometry for our sample of cool white dwarfs is compared to
current white dwarf models.

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The categories of this paper are: ao-sci
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The categories of this paper are: physics
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-bio
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: chem-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: math-ph
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The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas