The temperatures of red supergiants in low-metallicity environments

  title={The temperatures of red supergiants in low-metallicity environments},
  author={Gemma Gonz'alez-Tora and Ben Davies and Rolf Peter Kudritzki and Bertrand Plez},
The temperatures of red supergiants (RSGs) are expected to depend on metallicity (Z) in such a way that lower-Z RSGs are warmer. In this work, we investigate the Z-dependence of the Hayashi limit by analysing RSGs in the low-Z galaxy Wolf-Lundmark-Mellote (WLM), and compare with the RSGs in the higher-Z environments of the Small Magellanic Cloud (SMC) and Large Magellanic Cloud (LMC). We determine the effective temperature (Teff) of each star by fitting their spectral energy distributions, as… 

Red Supergiant Stars in IC 1613 and Metallicity-dependent Mixing Length in the Evolutionary Model

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We use moderate-resolution optical spectrophotometry and the new MARCS stellar atmosphere models to determine the effective temperatures of 74 Galactic red supergiants (RSGs). The stars are mostly

Spectral type, temperature and evolutionary stage in cool supergiants

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Red Supergiants (RSGs) are cool (∼4000 K), highly luminous stars ( L ∼ 10 5 ?> L ⊙ ?> ), and are among the brightest near-IR sources in star-forming galaxies. This makes them powerful probes of the

The ‘red supergiant problem’: the upper luminosity boundary of Type II supernova progenitors

By comparing the properties of red supergiant (RSG) supernova (SN) progenitors to those of field RSGs, it has been claimed that there is an absence of progenitors with luminosities L above log (L/L⊙)

A new survey of cool supergiants in the Magellanic Clouds

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

Red Supergiants as Cosmic Abundance Probes: Massive Star Clusters in M83 and the Mass–Metallicity Relation of Nearby Galaxies

We present an abundance analysis of seven super star clusters in the disk of M83. The near-infrared spectra of these clusters are dominated by red supergiants, and the spectral similarity in the