Red Clump stars in the Boötes III stellar system
نویسنده
چکیده
We report on the detection of a population of Red Clump (RC) stars probably associated with the recently discovered stellar system Boötes III. The RC is identified as a 3σ peak in the Luminosity Function (LF) of colour-selected stars extracted from the SDSS database. The peak is consistently detected in the g, r, i and z LFs at the expected luminosity of a typical RC at the distance of Boötes III. Moreover the stars around the LF peak show a maximum of surface density nearly coincident with the reported center of the system. Assuming that the detected feature is the genuine RC of Boötes III, we find that the system has the HB morphology typical of old and metal-poor dwarf spheroidals, it has an integrated magnitude MV ≃ −5.8 ± 0.5 and an ellipticity ǫ ∼ 0.5, quite typical of the recently identified new class of very faint dwarf galaxies.
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