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تسجيل مستخدم جديدSgr dSph: a bridge between Dwarf Galaxies and DLAs?
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L. Sbordone
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We present abundances for 12 giants in the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph) obtained from VLT - UVES spectra. Moving on a short period, polar orbit around the Milky Way, the Sgr dSph is undergoing tidal disruption and will eventually dissolve in the Halo.Our sample is dominated by a metal rich, alpha-element-poor population, indicative of long chemical processing of the dSph gas during a slow, probably bursting star formation history. This population is the most metal-rich ever observed in a Dwarf Galaxy of the Local Group, and has the lowest alpha-element content. Placing the known abundances of the LG dwarfs on the [alpha/Fe] vs. [Fe/H] plane allows now to recognize a well defined evolutive sequence, different from the one followed by the MW disk stars, but apparently superimposed to the one followed by many of the Damped Lyman Alpha systems.
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We report on abundances of O, Mg, Si, Ca and Fe for 10 giants in the Sgr dwarf spheroidal derived from high resolution spectra obtained with UVES at the 8.2m Kueyen-VLT telescope. The iron abundance spans the range -0.8 <[Fe/H] < 0.0 and the dominant
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