J/A+A/578/A3 New survey of supergiants in the MCs (Gonzalez-Fernandez+, 2015)
A new survey of cool supergiants in the Magellanic Clouds.
Gonzalez-Fernandez C., Dorda R., Negueruela I., Marco A.
<Astron. Astrophys. 578, A3 (2015)>
=2015A&A...578A...3G 2015A&A...578A...3G
ADC_Keywords: Magellanic Clouds ; Stars, supergiant ; Stars, variable ;
Photometry, infrared ; Spectroscopy ; MK spectral classification
Keywords: stars: supergiants - stars: massive - stars: late-type -
stars: AGB and post-AGB - Magellanic Clouds - surveys
Abstract:
In this study, we conduct a pilot program aimed at the red supergiant
population of the Magellanic Clouds. We intend to extend the current
known sample to the unexplored low end of the brightness distribution
of these stars, building a more representative dataset with which to
extrapolate their behaviour to other Galactic and extra-galactic
environments.
We select candidates using only near infrared photometry, and with
medium resolution multi-object spectroscopy, we perform spectral
classification and derive their line-of-sight velocities, confirming
the nature of the candidates and their membership to the clouds.
Around two hundred new RSGs have been detected, hinting at a yet to be
observed large population. Using near and mid infrared photometry we
study the brightness distribution of these stars, the onset of
mass-loss and the effect of dust in their atmospheres. Based on this
sample, new a priori classification criteria are investigated,
combining mid and near infrared photometry to improve the
observational efficiency of similar programs as this.
Description:
Observations were carried out with AAOmega at the Anglo-Australian
Telescope as backup/filler for a longer programme aimed at the inner
disc of the Milky Way during 9 nights between 2010 and 2013.
Table A1 contents spectral classification and NIR-MIR photometry for
all the observed candidates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 119 1008 Catalogue of the observed sources
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See also:
J/AJ/126/2867 : Red supergiants in Magellanic Clouds (Massey+, 2003)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Source designation (1)
13- 15 A3 --- Cl [LMC SMC] Large or Small Magellanic Cloud
17- 27 F11.8 deg RAdeg Right ascension (J2000.0) from 2MASS
29- 40 F12.8 deg DEdeg Declination (J2000.0) from 2MASS
42- 47 A6 --- Origin Origin of the object (2)
49- 51 A3 --- Var [Yes/No Unk] Spectral variability detected in
this work (3)
53- 57 F5.1 km/s HV [-60/338] Heliocentric velocity
60- 63 A4 --- SpT MK spectral type (4)
65- 70 A6 --- LC Luminosity class ("C" indicates a Carbon star)
72 I1 --- N0 [0/3] Number of nights in 2010
74 I1 --- N1 [0/1] Number of nights in 2011
76 I1 --- N2 [0/2] Number of nights in 2012
78 I1 --- N3 [0/1] Number of nights in 2013
80- 84 F5.2 mag Jmag [5.9/12.7]?=99.99 2MASS J magnitude
86- 90 F5.2 mag Hmag [5.2/11.5]?=99.99 2MASS H magnitude
92- 96 F5.2 mag Ksmag [4.7/11.1]?=99.99 2MASS Ks magnitude
98-102 F5.2 mag W1mag [4.7/11.0]?=- WISE W1 magnitude
104-108 F5.2 mag W2mag [4.3/11.1]?=- WISE W2 magnitude
110-114 F5.2 mag W3mag [3.9/11.8]?=- WISE W3 magnitude
116-119 F4.2 mag W4mag [1.4/10.0]?=- WISE W4 magnitude
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Note (1): For stars that show spectral variability, different epochs are
recorded as different entries.
Note (2): Origin code as follows:
GDN = our photometrically selected sample
Massey = from Massey & Olsen, 2003AJ....126.2867M 2003AJ....126.2867M, Cat. J/AJ/126/2867,
and references therein
YSG = from Neugent et al. (2010ApJ...719.1784N 2010ApJ...719.1784N, Cat. J/ApJ/719/1784)
Note (3): Does the star show spectral variability? For stars with only one
epoch, this is unknown ("Unk").
Note (4): "Unk" marks stars whose spectral type is unknown, either because
of low S/N or the fact that they are Carbon stars.
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Acknowledgements:
Carlos Gonzalez-Fernandez, cgonzal(at)ast.cam.ac.uk
(End) Patricia Vannier [CDS] 13-Apr-2015