The age and abundance structure of the stellar populations in the central sub-kpc of the Milky Way
Abstract
The four main findings about the age and abundance structure of the Milky Way bulge based on microlensed dwarf and subgiant stars are: (1) a wide metallicity distribution with distinct peaks at [Fe/H] = -1.09, -0.63, -0.20, +0.12, +0.41; (2) a high fraction of intermediate-age to young stars where at [Fe/H] > 0 more than 35 % are younger than 8 Gyr, (3) several episodes of significant star formation in the bulge 3, 6, 8, and 11 Gyr ago; (4) the `knee' in the α-element abundance trends of the sub-solar metallicity bulge appears to be located at a slightly higher [Fe/H] (about 0.05 to 0.1 dex) than in the local thick disk.
- Publication:
-
Rediscovering Our Galaxy
- Pub Date:
- August 2018
- DOI:
- 10.1017/S1743921317007426
- arXiv:
- arXiv:1707.05960
- Bibcode:
- 2018IAUS..334...86B
- Keywords:
-
- Galaxy: disk;
- Galaxy: evolution;
- Galaxy: structure;
- Galaxy: abundances;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 4 pages, contributed talk at the IAU Symposium 334 "Rediscovering our Galaxy" in Potsdam, July 10-14, 2017