|Speaker:||Giuseppe Bono (University of Rome Tor Vergata -- JSPS Fellow University of Tokyo)|
|Title:||A new spin on the stellar content of the Carina dSph galaxy|
|Date (JST):||Wed, Feb 03, 2016, 13:30 - 14:30|
|Place:||Seminar Room A|
Nearby dwarf galaxies are fundamental laboratories to address several astrophysical and cosmological problems. We focus our attention on the stellar content of the Carina dSph galaxy and discuss recent findings based photometric and spectroscopic data. We address the metallicity distribution of both old and intermediate-age stellar populations using high and medium resolution spectra collected at the ESO/VLT (UVES, FLAMES/GIRAFFE). The use of new photometric diagnostic (c_UBI=(U B)-(B I)) allowed us, for the first time, to separate old and intermediate-age red giant stars. We found that the quoted stellar populations display distinct [Fe/H] and [Mg/H] distributions: their mean iron abundances are –2.13+-0.06 dex (sigma=0.28), and –1.74+-0.03 dex (sigma=0.20). Moreover, we found that the two stellar populations have different [Mg/H] abundances: –1.77+-0.08 dex (sigma=0.36) and –1.37+-0.04 dex (sigma=0.27).
We also mention preliminary results concerning the Carina kinematics and the impact that the new results have on the Mass-Metallicity relation and on the Faber-Jackson relation. Finally, we briefly outline the role that cluster and field RR Lyrae stars play to constrain the early formation and evolution of the Galactic Halo.