相关论文: Baade's window with APOGEE: Metallicities, ages an…
We present stellar age distributions of the Milky Way (MW) bulge region using ages for $\sim$6,000 high-luminosity ($\log(g) < 2.0$), metal-rich ($\rm [Fe/H] \ge -0.5$) bulge stars observed by the Apache Point Observatory Galactic Evolution…
The Galactic bulge has a bimodal metallicity distribution function: different kinematic, spatial, and, potentially, age distributions characterize the metal-poor and metal-rich components. Despite this observed dichotomy, which argues for…
We seek to constrain the formation of the Galactic bulge by means of analysing the detailed chemical composition of a large sample of red clump stars in Baade's window. We measure [Fe/H] in a sample of 219 bulge red clump stars from R=20000…
The age and chemical characteristics of the Galactic bulge link to the formation and evolutionary history of the Galaxy. Data-driven methods and large surveys enable stellar ages and precision chemical abundances to be determined for vast…
We exploit the [Mg/Mn]-[Al/Fe] chemical abundance plane to help identify nearby halo stars in the 14th data release from the APOGEE survey that have been accreted on to the Milky Way. Applying a Gaussian Mixture Model, we find a `blob' of…
Large scale surveys open the possibility to investigate Galactic evolution both chemically and kinematically, however, reliable stellar ages remain a major challenge. Detailed chemical information provided by high-resolution spectroscopic…
The Galactic Bulge has long been assumed to be a largely old stellar population. However, some recent studies based on observations with the HST WF/PC-1 and WFPC2 of stars in the Galactic Bulge have concluded that the old population may not…
The central part of the Galaxy host a multitude of stellar populations, including the spheroidal bulge stars, stars moved to the bulge through secular evolution of the bar, inner halo, inner thick disk, inner thin disk, as well as debris…
[ABRIDGED] Based on high-resolution (R~42000 to 48000) and high signal-to-noise (S/N~50 to 150) spectra obtained with UVES/VLT, we present detailed elemental abundances (O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, Y, and Ba) and stellar ages…
Despite its importance for understanding the nature of early stellar generations and for constraining Galactic bulge formation models, at present little is known about the metal-poor stellar content of the central Milky Way. This is a…
We obtained stellar ages and metallicities via spectrum fitting for a sample of 575 bulges with spectra available from the Sloan Digital Sky Survey. The structural properties of the galaxies have been studied in detail in Gadotti (2009b)…
We present detailed abundance results for 9 Galactic bulge stars in Baade's Window, based on HIRES (R=45,000--60,000) spectra taken with the Keck I telescope. The alpha elements show non-uniform enhancements relative to the Solar…
In the coming years, detailed chemical abundances from large-scale high-resolution spectroscopic surveys will become available for vast numbers of stars across the Milky Way. Previous work has suggested that abundance ratios from these…
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) provides spectroscopic information of regions of the inner Milky Way inaccessible to optical surveys. We present the first large study of the metallicity distribution of…
The bar/bulge and inner disk are fundamental building blocks of the Milky Way, containing a large fraction of its stellar mass. However, stars in these regions are faint, crowded, and have high extinction, which makes studying their…
Over the last few years, many studies have found an empirical relationship between the abundance of a star and its age. Here we estimate spectroscopic stellar ages for 178 825 red-giant stars observed by the APOGEE survey with a median…
Bulge globular clusters(BGCs) are exceptional tracers of the formation and chemodynamical evolution of this oldest Galactic component. However, until now, observational difficulties have prevented us from taking full advantage of these…
We report detailed chemical abundance analysis of 27 RGB stars towards the Galactic bulge in Baade's Window for elements produced by massive stars: O, Na, Mg, Al, Si, Ca and Ti. All of these elements are overabundant in the bulge relative…
The Milky Way bulge-bar is composed of multiple populations. Using chemical and kinematical planes, we segregate six populations in a bulge-bar sample observed by the APOGEE survey: two with bar-driven orbits, two with eccentric orbits, and…
We compare abundance ratio trends in a sample of $\sim 11,000$ Milky Way bulge stars ($R_{\rm GC} < 3$ kpc) from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) to those of APOGEE stars in the Galactic disk ($5$ kpc $<…