The distance to the Sagittarius dwarf spheroidal galaxy from the red giant branch tip

Abstract

We derived the distance to the central region of the Sagittarius (Sgr) dwarf spheroidal galaxy from the red giant branch tip. The obtained distance modulus is (m - M)0 = 17.10 ± 0.15, corresponding to a heliocentric distance D = 26.30 ± 1.8 Kpc. This estimate is in good agreement with the distance obtained from RR Lyrae (RR Ly) stars of the globular cluster M 54, located in the core of the Sgr galaxy, once the most accurate estimate of the cluster metallicity and the most recent calibration of the MV(RR Ly) versus [Fe/H] relation are adopted.