Back to Volume
Paper: Evidence of a Chemical Difference Between the Galactic Center and the Surrounding Inner Bulge Stellar Populations
Volume: 528, New Horizons in Galactic Center Astronomy and Beyond
Page: 377
Authors: Schultheis, M.
Abstract: Although there have been numerous studies of chemical abundances in the Galactic bulge, the central two degrees have been relatively unexplored due to the heavy and variable interstellar extinction, extreme stellar crowding, and the presence of a complex foreground disk stellar population. We used a compilation of recent measurements of metallicities derived from medium-high resolution spectroscopy and compare those metallicities with low-resolution studies. Defining "metal-rich" as stars with [Fe/H]>0, and "metal-poor" as stars with [Fe/H]<0, we find compelling evidence for a higher fraction (∼ 80%) of metal-rich stars in the Galactic Center (GC) compared to the values (50-60%) measured in the low latitude fields within the innermost 600 pc. The high fraction of metal-rich stars in the GC region implies a very high mean metallicity of +0.2 dex, while in the inner 600 pc of the bulge the mean metallicity is rather homogenous around the solar value.
Back to Volume