J/A+A/532/A69 Spectra of 6 SBS stars (Rossi+, 2011)
Revised classification of the SBS carbon star candidates including the discovery
of a new emission line dwarf carbon star.
Rossi C., Gigoyan K.S., Avtandilyan M.G., Sclavi S.
<Astron. Astrophys. 532, A69 (2011)>
=2011A&A...532A..69R 2011A&A...532A..69R
ADC_Keywords: Stars, carbon ; Stars, M-type ; Spectroscopy
Keywords: surveys - stars: carbon - stars: individual: SBS 1310+561
Abstract:
Faint high latitude carbon stars are rare objects commonly thought to
be distant, luminous giants. For this reason they are often used to
probe the structure of the Galactic halo; however more accurate
investigation of photometric and spectroscopic surveys has revealed an
increasing percentage of nearby objects with luminosities of main
sequence stars. We analyzed new optical spectra and photometry and
used astronomical databases available on the web, aiming at clarifying
the nature of the ten carbon star candidates present in the General
Catalogue of the Second Byurakan Survey.
We verified that two stars are N-type giants already confirmed by
other surveys. We found that four candidates are M-type stars and
confirmed the carbon nature of the remaining four stars; the
characteristics of three of them are consistent with an early CH giant
type. The fourth candidate, SBS 1310+561 identified with a high proper
motion star, is a rare type of dwarf carbon showing emission lines in
its optical spectrum. We estimated absolute magnitudes and distances
to the dwarf carbon and the CH stars. Our limited sample confirmed the
increasing evidence that spectroscopy or colour alone are not
conclusive luminosity discriminants for CH-type carbon stars.
Description:
The spectra of four C star candidates (SBS 0759+533, SBS 1310+561,
1543+555, SBS 1701+555) and two M stars (SBS 0854+530, SBS 1444+503)
are presented. The data were collected with different telescopes and
resolutions (see references).
In each file abscissae are wavelength in Angstrom and ordinates are
extinction corrected intensities (in counts) normalized to the
maximum.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 53 8 Star's list
spectra/* . 8 Individual spectra
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [SBS]
4- 11 A8 --- SBS SBS name (HHMM+DDd)
14- 15 I2 h RAh Hour of Right Ascension (J2000.0)
17- 18 I2 min RAm Minute of Right Ascension (J2000.0)
20- 23 F4.1 s RAs Second of Right Ascension (J2000.0)
25 A1 --- DE- Sign of Declination (J2000.0)
26- 27 I2 deg DEd Degree of Declination (J2000.0)
29- 30 I2 arcmin DEm Arcminute of Declination (J2000.0)
32- 33 I2 arcsec DEs Arcsecond of Declination (J2000.0)
36- 38 A3 --- SpType MK spectral type
41- 53 A13 --- FileName Name of the file containing the spectrum in
subdirectory spectra
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Byte-by-byte Description of file(#): spectra/*
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Bytes Format Units Label Explanations
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1- 10 F10.2 0.1nm lambda Wavelength
13- 20 F8.5 ct Int Extinction corrected intensities (in counts)
normalized to the maximum (1)
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Note (1): Correction for Galactic extinction according to Schlegel et al.
(1998ApJ...500..525S 1998ApJ...500..525S)
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Acknowledgements:
Corinne Rossi, corinne.rossi(at)uniroma1.it
References:
AFOSC USER MANUAL
http://www.pd.astro.it/asiago/5000/5100/5100.html
BFOSC USER MANUAL
http://www.bo.astro.it/~loiano/TechPage/bfosceng/BFOSC.html
(End) Corinne Rossi [Univ. La Sapienza Roma], Patricia Vannier [CDS] 01-Jul-2011