A new Milky Way halo star cluster in the Southern Galactic Sky
  We report on the discovery of a new Milky Way companion stellar system
located at (RA, Dec) = (22h10m43.15s, +14:56:58.8). The discovery was made
using the eighth data release of SDSS after applying an automated method to
search for overdensities in the Baryon Oscillation Spectroscopic Survey
footprint. Follow-up observations were performed using CFHT-MegaCam, which
reveal that this system is comprised of an old stellar population, located at a
distance of 31.9+1.0-1.6 kpc, with a half-light radius of r_h = 7.24+1.94-1.29
pc and a concentration parameter of c = 1.55. A systematic isochrone fit to its
color-magnitude diagram resulted in log(age) = 10.07+0.05-0.03 and [Fe/H] =
-1.58+0.08-0.13 . These quantities are typical of globular clusters in the MW
halo. The newly found object is of low stellar mass, whose observed excess
relative to the background is caused by 96 +/- 3 stars. The direct integration
of its background decontaminated luminosity function leads to an absolute
magnitude of MV = -1.21 +/- 0.66. The resulting surface brightness is uV = 25.9
mag/arcsec2 . Its position in the M_V vs. r_h diagram lies close to AM4 and
Koposov 1, which are identified as star clusters. The object is most likely a
very faint star cluster - one of the faintest and lowest mass systems yet
identified.
