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Building up the Galactic Halo: The Sagittarius dSph and the globular cluster M22

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

The Sagittarius dwarf spheroidal (Sgr) and a few paculiar Galactic Globular Clusters (GGC) can be considered as building blocks of theGalactic Halo. We present a series of results based on a wide field photometry of the Sgr system and the GGC M22. In particular for Sgr we present: (1) the detection of the RGB-bump, a feature that together with the shape of the RGB can be used to constrain the allowed range of age and metallicity and (2) the detection of a clear blue horizontal branch which probes the existance of a metal poor population. In the case of M22 we present clear evidence that differential reddening is the primary cause for the observed spread of the evolutionary sequences.

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L. Monaco, F. R. Ferraro, M. Bellazzini, E. Pancino. 2003-05-07. Building up the Galactic Halo: The Sagittarius dSph and the globular cluster M22. https://arxiv.org/abs/astro-ph/0305107

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