J/A+A/664/A45 Characterisation of Galactic carbon stars (Abia+, 2022)
Characterisation of Galactic carbon stars and related stars from Gaia EDR3.
Abia C., de Laverny P., Romero M., Figueras F.
<Astron. Astrophys. 664, A45 (2022)>
=2022A&A...664A..45A 2022A&A...664A..45A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, carbon ; Photometry, infrared ; Stars, distances ;
Radial velocities
Keywords: stars: late type - stars: carbon - techniques: miscellaneous
Abstract:
The third early Gaia data release (EDR3) has improved the accuracy of
the astrometric parameters of numerous long-period variable (LPV)
stars. Many of these stars are on the asymptotic giant branch (AGB),
showing either a C-rich or O-rich envelope and are characterised by
high luminosity, changing surface composition, and intense mass loss.
This make them very useful for stellar studies. In a previous
investigation, we used Gaia DR2 astrometry to derive the luminosity
function, kinematic properties, and stellar population membership of a
flux-limited sample of carbon stars in the solar neighbourhood of
different spectral types. Here, we extend this initial study to more
recent surveys with a greater number of Galactic carbon stars and
related stars by adopting the more accurate EDR3 astrometry
measurements. Based on a much larger statistics, we confirm that N-
and SC-type carbon stars share a very similar luminosity function,
while the luminosities of J-type stars (Mbol) are fainter by half a
magnitude on average. R-hot type carbon stars have luminosities
throughout the RGB, which favours the hypothesis of an external origin
for their carbon enhancement. Moreover, the kinematic properties of a
significant fraction of the R-hot stars are compatible with the
thick-disc population, in contrast with that of N- and SC-type stars,
which would belong mostly to the thin disk. We also derive the
luminosity function of a large number of Galactic extrinsic and
intrinsic (O-rich) S stars and show that the luminosities of the
latter are typically higher than the predicted onset of the third
dredge-up during the AGB for solar metallicity. This result is
consistent with these stars being genuine thermally pulsing AGB stars.
On the other hand, using the so-called Gaia-2MASS diagram, we show
that the overwhelming majority of the carbon stars identified in the
LAMOST survey as AGB stars are probably R-hot and/or CH-type stars.
Finally, we report the identification of 2660 new carbon stars
candidates that we identified through their 2MASS photometry, their
Gaia astrometry, and their location in the Gaia-2MASS diagram.
Description:
Photometric, kinematic and luminosity parameters are given for a
sample of about 1000 Galactic stars of N, SC, J, R and S (intrinsic
and extrinsic) spectral types. For each star names, Gaia EDR3
identification, extinction values Av from Lallement et al.
(2019A&A...625A.135L 2019A&A...625A.135L, Cat. J/A+A/625/A135), Drimmel et al
(2003A&A...409..205D 2003A&A...409..205D), and Green et al. (2019ApJ...887...93G 2019ApJ...887...93G), Jo
magnitude, Kso magnitude, distance, bolometric luminosity,
Z-coordinate above/below the Galactic plane, galactocentric distance,
velocity components and population membership are given.
In appendix, the Gaia EDR3 identification is given for 520 newly
discovered carbon stars after cross-matching with the 2MASS catalogue.
Some of them were previously quoted as possible carbon stars, which
our analysis validates. The stars placed in the region of extreme
C-rich (see Fig. 14 in the paper) are excluded from this latter list
since their magnitudes could be affected by circumstellar extinction
and, therefore, their absolute K magnitude could be uncertain.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 155 827 Photometric, kinematic and luminosity parameters
for a sample of Galactic stars of N, SC, J, R
and S (intrinsic and extrinsic) spectral types
ncstars.dat 29 520 Gaia EDR3 identification of newly discovered
carbon stars (corrected version, 14/11/2023)
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See also:
I/350 : Gaia EDR3 (Gaia Collaboration, 2020)
J/A+A/625/A135 : Galactic interstellar dust Gaia-2MASS 3D maps
(Lallement,+ 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Type Spectral type
15- 33 A19 --- Name Name of the star
37- 55 I19 --- GaiaEDR3 Gaia EDR3 source_id
58- 62 F5.3 mag Av1 Extinction from Lallement et al.
(2019A&A...625A.135L 2019A&A...625A.135L, Cat. J/A+A/625/A135)
65- 69 F5.3 mag Av2 ? Extinction from Drimmel et al.
(2003A&A...409..205D 2003A&A...409..205D)
72- 76 F5.3 mag Av3 ? Extinction from Green et al.
(2019ApJ...887...93G 2019ApJ...887...93G)
78- 82 F5.2 mag Jomag ? J-band magnitude (1)
85- 89 F5.2 mag Ksomag ? Ks-band magnitude (1)
93-100 F8.2 pc d Distance
105-109 F5.2 mag Mbol ? Bolometric magnitude
112-117 F6.3 kpc Z ? Z-coordinate
121-125 F5.2 kpc R ? Galactocentric distance
128-134 F7.2 km/s Vr ? Radial velocity component
139-144 F6.2 km/s Vp ? Rotational velocity component
146-152 F7.2 mag Mbol2 ? Bolometric magnitude repeated
155 I1 --- Pop ? Population membership (2)
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Note (1): The Jo and Kso magnitudes are those corrected for extinction according
to Lallement et al. (2019A&A...625A.135L 2019A&A...625A.135L, Cat. J/A+A/625/A135).
Note (2): Membership probability as follows:
0 = higher than 80% for thin disc
1 = thick disc
2 = halo
blank = ambiguous or no Gaia DR2 Vrad available
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Byte-by-byte Description of file: ncstars.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- --- [Gaia EDR3]
11- 29 I19 --- GaiaEDR3 Gaia EDR3 identification
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Acknowledgements:
Carlos Abia, cabia(at)ugr.es
History:
03-Aug-2022: on-line version
14-Nov-2023: corrected version of ncstars.dat file
(End) Patricia Vannier [CDS] 02-Jun-2022