Red Supergiant Stars as Cosmic Abundance Probes: KMOS Observations in
  NGC 6822
  We present near-IR spectroscopy of red supergiant (RSG) stars in NGC 6822,
obtained with the new VLT-KMOS instrument. From comparisons with model spectra
in the J-band we determine the metallicity of 11 RSGs, finding a mean value of
[Z] = -0.52 $\pm$ 0.21 which agrees well with previous abundance studies of
young stars and HII 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 with recent evolutionary models.
