Resumen
The Sagittarius dwarf spheroidal (Sgr dSph) galaxy is a Milky Way satellite currently merging with the parent system. This small galaxy is undergoing disruption due to tidal forces, while stars and clusters lost along the orbit progressively mix with the general Galactic population. The Sgr system is also one of the very few local dSph's known to host stellar clusters, but the census of its cluster population is far from complete. This is very bad, both because the total amount of clusters can help estimating the mass of the original system, and because the age-metallicity relations of the so-far confirmed six members shows an age gap at intermediate ages similar to the well-known gap of the Large Magellanic Cloud. Still, this feature could be due only to the small number of confirmed members. Here we show the status of our project aimed at testing the membership to the Sgr galaxy of a series of candidates proposed in the literature. Our recent spectroscopic studies could exclude the Sgr membership of three candidates, namely Ruprecht 106, NGC 4147, and E 3, although a follow-up study of the latter is ongoing to confirm the previous results. On the other hand, our chemical analysis concluded that NGC 5634 is very likely a member of the Sgr cluster family, and NGC 5053 also could be. Finally, we present our preliminary results of our spectroscopic analysis for the last object, namely AM 4. This candidate is particularly important, because previous estimates of age and metallicity indicate that it closely follow the relation traced by confirmed clusters, but its intermediate age makes it fall exactly at the middle of the supposed age gap.
