Abstract Details
| Name: Deepak Deepak Affiliation: IIA, Bengaluru Conference ID: ASI2019_289 Title : The Galactic Halo: Stellar Populations and Formation History Authors and Co-Authors : Deepak; Bacham E. Reddy; David L. Lambert Abstract Type : Oral Abstract Category : Stars, ISM and Galaxy Abstract : The halo of the Milky Way is understood to be formed early on from a mixture of dissipative collapse and accretion. Chemically, it is predominantly metal-poor and enriched in the alpha-elements. It has been shown to split into two chemically distinct components. Recent studies have reported the presence of alpha-poor stars in halo samples. These studies have shown that the alpha-poor sequence is distinct in kinematics, ages, and other chemical elements (e.g., C, Na, and Cu) compared to the alpha-rich sequence. The alpha-rich stars may have formed in situ. It is thought that the alpha-poor sequence is assembled through the accretion of satellite galaxies. Kinematically, this population tends to move on retrograde orbits with rather small values of the vertical component (W) to the Galactic velocity but a large spread in the velocity component (U) toward the Galactic center. In this talk, we plan to present preliminary results from our ongoing study of the galactic halo using large spectroscopic and astrometric surveys. Depending on these results we also plan to speculate on its formation and evolution history. |