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The distance to the Sgr dwarf spheroidal galaxy from the Red Giant Branch Tip

L. Monaco·M. Bellazzini·F. R. Ferraro·E. Pancino
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Abstract

We derived the distance to the central region of the Sagittarius dwarf spheroidal galaxy from the Red Giant Branch Tip. The obtained distance modulus is $(m-M)_0=17.10\pm0.15$, corresponding to a heliocentric distance $D=26.30\pm1.8$ Kpc. This estimate is in good agreement with the distance obtained from RR Lyrae 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 $M_V(RRLy) vs.[Fe/H]$ relation are adopted.

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L. Monaco, M. Bellazzini, F. R. Ferraro, E. Pancino. 2004-06-15. The distance to the Sgr dwarf spheroidal galaxy from the Red Giant Branch Tip. https://doi.org/10.1111/j.1365-2966.2004.08122.x

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