Red supergiant stars as cosmic abundance probes: KMOS observations in NGC 6822

L. R. Patrick, C. J. Evans, B. Davies, R. P. Kudritzki, J. Z. Gazak, M. Bergemann, B. Plez, A. M N Ferguson

Research output: Contribution to journalArticlepeer-review

Abstract / Description of output

We present near-IR spectroscopy of red supergiant (RSG) stars in NGC 6822, obtained with the new K-band Multi-Object Spectrograph Very Large Telescope, Chile. From comparisons with model spectra in the J-band we determine the metallicity of 11 RSGs, finding a mean value of [Z] = -0.52 ± 0.21, which agrees well with previous abundance studies of young stars and H ii regions. We also find an indication for a low-significance abundance gradient within the central 1 kpc. We compare our results with those derived from older stellar populations and investigate the difference using a simple chemical evolution model. By comparing the physical properties determined for RSGs in NGC 6822 with those derived using the same technique in the Galaxy and the Magellanic Clouds, we show that there appears to be no significant temperature variation of RSGs with respect to metallicity, in contrast to recent evolutionary models.

Original languageEnglish
Article number14
JournalAstrophysical Journal
Volume803
Issue number1
DOIs
Publication statusPublished - 7 Apr 2015

Keywords / Materials (for Non-textual outputs)

  • Galaxies: individual (NGC 6822)
  • Stars: abundances
  • Stars: supergiants

Fingerprint

Dive into the research topics of 'Red supergiant stars as cosmic abundance probes: KMOS observations in NGC 6822'. Together they form a unique fingerprint.

Cite this