J/AJ/124/1651 Faint high-latitude carbon stars SDSS photometry (Margon+, 2002)
Faint high-latitude carbon stars discovered by the Sloan Digital Sky Survey:
methods and initial results.
Margon B., Anderson S.F., Harris H.C., Strauss M.A., Knapp G.R., Fan X.,
Schneider D.P., Vanden Berk D.E., Schlegel D.J., Deutsch E.W., Ivezic Z.,
Hall P.B., Williams B.F., Davidsen A.F., Brinkmann J., Csabai I.,
Hayes J.J.E., Hennessy G., Kinney E.K., Kleinman S.J., Lamb D.Q., Long D.,
Neilsen E.H., Nichol R., Nitta A., Snedden S.A., York D.G.
<Astron. J. 124, 1651 (2002)>
=2002AJ....124.1651M 2002AJ....124.1651M
ADC_Keywords: Stars, carbon ; Stars, faint ; Photometry, SDSS ;
Photometry, infrared
Keywords: astrometry - stars: carbon - stars: statistics - surveys
Abstract:
We report the discovery of 39 faint high-latitude carbon stars (FHLCs)
from Sloan Digital Sky Survey (SDSS) commissioning data. The objects,
each selected photometrically and verified spectroscopically, range
over 16.6<r*<20.0 and show a diversity of temperatures as judged
by both colors and NaD line strengths. Although a handful of these
stars were previously known, these objects are, in general, too faint
and too warm to be effectively identified in other modern surveys such
as the Two Micron All Sky Survey, nor are their red/near-IR colors
particularly distinctive. We present proper-motion measures for each
object, indicating that the sample is a mixture of extremely distant
(greater than 100kpc) halo giant stars, useful for constraining halo
dynamics, and members of the recently recognized exotic class of very
nearby dwarf carbon (dC) stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 68 39 Faint high-latitude carbon stars discovered in
SDSS commissioning data
table2.dat 74 17 SDSS faint high-latitude carbon stars in
released 2MASS fields
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See also:
II/246 : The 2MASS database (IPAC/UMass, 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- SDSS SDSS designation
18- 22 F5.2 mag r*mag SDSS r* magnitude
24- 27 F4.2 mag u*-g* SDSS u*-g* colour index
29- 32 F4.2 mag g*-r* SDSS g*-r* colour index
34- 37 F4.2 mag r*-i* SDSS r*-i* colour index
39- 43 F5.2 mag i*-z* SDSS i*-z* colour index
45- 47 I3 mas/yr pm ? Proper motion
49- 50 I2 mas/yr e_pm ? rms uncertainty on pm
52- 54 I3 deg PA ? Position angle
56- 61 F6.1 km/s HRV ? Heliocentric radial velocity
63- 66 F4.1 km/s e_HRV ? rms uncertainty on HRV
68 A1 --- n_SDSS [b-d] Individual notes (1)
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Note (1): Notes are coded as follows:
b: Two separate observations exist; the weighted average RV is quoted
c: ARC 3.5m spectrum only; no RV data is available
d: The object is very faint; there is no suitable first-epoch data
for quantitative proper-motion analysis, although informal
indications are that any motion must be small
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- SDSS SDSS designation
17 A1 --- n_SDSS [c] Note on SDSS (2)
19- 33 A15 --- 2MASS 2MASS designation (1)
34 A1 --- n_2MASS [b] Note on 2MASS (2)
36- 40 F5.2 mag z*mag SDSS z* magnitude
42- 46 F5.2 mag Jmag ? 2MASS J Magnitude
48- 51 F4.2 mag e_Jmag ? rms uncertainty on Jmag
53- 57 F5.2 mag Hmag ? 2MASS H magnitude
59- 62 F4.2 mag e_Hmag ? rms uncertainty on Hmag
64 A1 --- l_Kmag Limit flag on Kmag
65- 69 F5.2 mag Kmag ? 2MASS K magnitude
71- 74 F4.2 mag e_Kmag ? rms uncertainty on Kmag
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Note (1): Blank entry indicates object lies within 2MASS survey area,
but was not detected by 2MASS.
Note (2): Individual notes:
b: Faintly visible on sky GIF images, but not catalogued by 2MASS.
c: Not part of autonomously selected sample, but included here for
completeness; see Sect. 2.2.2 of the paper.
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History:
From electronic version of the journal
(End) James Marcout, Patricia Bauer [CDS] 08-Nov-2002