Evolved Massive Stars at Low-metallicity II. Red Supergiant Stars in the Small Magellanic Cloud

Abstract

We present the most comprehensive RSG sample for the SMC up to now, including 1,239 RSG candidates. The initial sample is derived based on a source catalog for the SMC with conservative ranking. Additional spectroscopic RSGs are retrieved from the literature, as well as RSG candidates selected from the inspection of CMDs. We estimate that there are in total $\sim$ 1,800 or more RSGs in the SMC. We purify the sample by studying the infrared CMDs and the variability of the objects, though there is still an ambiguity between AGBs and RSGs. There are much less RSGs candidates ($\sim$4\%) showing PAH emission features compared to the Milky Way and LMC ($\sim$15\%). The MIR variability of RSG sample increases with luminosity. We separate the RSG sample into two subsamples ("risky" and "safe") and identify one M5e AGB star in the "risky" subsample. Most of the targets with large variability are also the bright ones with large MLR. Some targets show excessive dust emission, which may be related to previous episodic mass loss events. We also roughly estimate the total gas and dust budget produced by entire RSG population as $\sim 1.9_{-1.1}^{+2.4}\times 10^{-6}{\mathrm{M}}_{\odot }/yr$ in the most conservative case. Based on the MIST models, we derive a linear relation between $T_{\mathrm{eff}}$ and observed $\mathrm{J}-{\mathrm{K}}_{\mathrm{S}}$ color with reddening correction for the RSG sample. By using a constant bolometric correction and this relation, the Geneva evolutionary model is compared with our RSG sample, showing a good agreement and a lower initial mass limit of $\sim$7 ${\mathrm{M}}_{\odot }$ for the RSG population. Finally, we compare the RSG sample in the SMC and the LMC. Despite the incompleteness of LMC sample in the faint end, the result indicates that the LMC sample always shows redder color (except for the $IRAC1-IRAC2$ and $WISE1-WISE2$ colors due to CO absorption) and larger variability than the SMC sample.

18 pages, 12 figures, A&A accepted

References in corpus (35)

• The Gaia mission
• Modules for Experiments in Stellar Astrophysics (MESA)
• Dust Masses, PAH Abundances, and Starlight Intensities in the SINGS Galaxy Sample
• The death of massive stars - I. Observational constraints on the progenitors of type II-P supernovae
• An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent
• The Optical to Mid-Infrared Extinction Law Based on the APOGEE, Gaia DR2, Pan-STARRS1, SDSS, APASS, 2MASS and WISE Surveys
• Spitzer SAGE Infrared Photometry of Massive Stars in the Large Magellanic Cloud
• The Effective Temperatures and Physical Properties of Magellanic Cloud Red Supergiants: The Effects of Metallicity
• Red supergiants as potential Type IIn supernova progenitors: Spatially resolved 4.6 micron CO emission around VY CMa and Betelgeuse
• Variability in red supergiant stars: pulsations, long secondary periods and convection noise
• Spitzer SAGE-SMC Infrared Photometry of Massive Stars in the Small Magellanic Cloud
• The Initial Masses of the Red Supergiant Progenitors to Type-II Supernovae
• The impact of mass-loss on the evolution and pre-supernova properties of red supergiants
• The dust condensation sequence in red super-giant stars
• Atmospheric dynamics and the mass loss process in red supergiant stars
• AGB stars in the Magellanic Clouds. II. The rate of star formation across the LMC
• Wolf-Rayet stars in the Small Magellanic Cloud: I. Analysis of the single WN stars
• The Magellanic zoo: Mid-infrared Spitzer spectroscopy of evolved stars and circumstellar dust in the Magellanic Clouds
• Molecules and dust production in the Magellanic Clouds
• The VMC survey - XXVI. Structure of the Small Magellanic Cloud from RR Lyrae stars
• Luminosities and mass-loss rates of Local Group AGB stars and Red Supergiants
• The evolution of Red Supergiants to supernova in the LMC cluster NGC 2100
• A Spitzer IRS Spectral Atlas of Luminous 8 micron Sources in the Large Magellanic Cloud
• The Period-Luminosity Relation of Red Supergiant Stars in the Small Magellanic Cloud
• Spitzer Infrared Spectrographic point source classification in the Small Magellanic Cloud
• Red Giants in the Small Magellanic Cloud. II. Metallicity Gradient and Age-Metallicity Relation
• A new survey of cool supergiants in the Magellanic Clouds
• Red Supergiant Stars in the Large Magellanic Cloud: I. The Period-Luminosity Relation
• The MOSDEF Survey: Metallicity Dependence of the PAH Emission at High Redshift and Implications for 24 micron-inferred IR Luminosities and Star Formation Rates at z~2
• Red Supergiants as Cosmic Abundance Probes: massive star clusters in M83, and the mass-metallicity relation of nearby galaxies
• The VLT-FLAMES Tarantula Survey. XXX. Red stragglers in the clusters Hodge 301 and SL 639
• The period-luminosity relation of red supergiants with Gaia DR2
• The Period-Luminosity Relations of Red Supergiants in M33 and M31
• Characterizing the Population of Bright Infrared Sources in the Small Magellanic Cloud
• A Spitzer/IRAC Characterization of Galactic AGB and RSG Stars

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• Red supergiants in M31 and M33 II. The Mass Loss Rate
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• Evolved Massive Stars at Low-metallicity IV. Using 1.6 $\mu$m "H-bump" to identify red supergiant stars: a case study of NGC 6822
• Investigating episodic mass loss in evolved massive stars: I. Spectroscopy of dusty massive stars in ten southern galaxies
• Red supergiant stars in binary systems. I. Identification and characterisation in the Small Magellanic Cloud from the UVIT ultraviolet imaging survey
• Properties of luminous red supergiant stars in the Magellanic Clouds
• Investigating the metallicity dependence of the mass-loss rate relation of red supergiants
• Investigating episodic mass loss in evolved massive stars: II. Physical properties of red supergiants at subsolar metallicity
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• Red Supergiants in the Milky Way and Nearby Galaxies
• A machine-learning photometric classifier for massive stars in nearby galaxies II. The catalog
• Dependence of pulsation mode of Cepheids on metallicity
• The Stripped-Star Ultraviolet Magellanic Cloud Survey (SUMS): The UV Photometric Catalog and Stripped Star Candidate Selection
• Locating Red Supergiants in the Galaxy NGC 6822