相关论文: Kinematics and Composition of the Galactic Bulge: …
The chemical evolution of the Galactic bulge is treated here in the context of an inside-out model for the Galaxy formation. We assume that this central region evolved even faster than the Galactic halo and test the effect of changing the…
In the context of a project aimed at characterizing the properties of star clusters in the Galactic bulge, here we present the determination of the internal kinematics and structure of the massive globular cluster NGC 6569. The kinematics…
Constraints on the Galactic bulge/bar structure and formation history from stellar kinematics and metallicities mainly come from relatively high-latitude fields (|b|>4) where a complex mix of stellar population is seen. We aim here to…
Radial velocities of 2768 fundamental mode RR Lyrae stars (RRLs) toward the Southern Galactic bulge are presented, spanning the southern bulge from -8 < l < +8 and -3 < b <-6. Distances derived from the pulsation properties of the RRLs are…
We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l,b)=(+5.25,-3.02) and (0,-12). The (+5.25,-3.02)…
Low-mass, variable, high-velocity stars are interesting study cases for many aspects of Galactic structure and evolution. Until recently, the only known high- or hyper-velocity stars were young stars thought to originate from the Galactic…
Context. The measurement of $\alpha$-elements abundances provides a powerful tool to put constraints on chemical evolution and star formation history of galaxies. The majority of studies on the $\alpha$-element Sulfur (S) are focused on…
The Galactic Bulge can uniquely be studied from large samples of individual stars, and is therefore of prime importance for understanding the stellar population structure of bulges in general. Here the observational evidence on the…
We investigate the rotation curve of the Milky Way using a multi-component mass model including a stellar disk, a gaseous disk, a bulge/bar component, and a dark-matter halo. The stellar and gas contributions are calibrated using recent…
We report a detailed investigation of the bulk motions of the nearby Galactic stellar disk, based on three samples selected from the LSS-GAC DR2: a global sample containing 0.57 million FGK dwarfs out to $\sim$ 2 kpc, a local subset of the…
We present a detailed elemental abundance study of 90 F and G dwarf, turn-off and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11…
We have used the AAOMEGA spectrograph to obtain R $\sim 1500$ spectra of 714 stars that are members of two red clumps in the Plaut Window Galactic bulge field $(l,b)=0^{\circ},-8^{\circ}$. We discern no difference between the clump…
In this work, we derive systemic velocities and subsequently orbits for 8456 RR~Lyrae stars. We identify interlopers from other Milky Way (MW) structures, which amount to 22 percent of the total sample. Most interlopers are associated with…
The kinematics of the Milky Way bulge is known to be complex, reflecting the presence of multiple stellar components with distinct chemical and spatial properties. In particular, the bulge hosts a bar structure exhibiting cylindrical…
AIMS: We spectroscopically characterize the Galactic Bulge to infer its star formation timescale, compared to the other Galactic components, through the chemical signature on its individual stars. METHODS: We derived iron and oxygen…
Recent studies of elemental abundances in the Galactic halo and in the Galactic disk have underscored the possibility to kinematically separate different Galactic subcomponents. Correlations between the galactocentric rotation velocity and…
We describe the motivation, field locations and stellar selection for the ARGOS spectroscopic survey of 28,000 stars in the bulge and inner disk of the Milky Way galaxy across latitudes of b = -5 deg to -10 deg. The primary goal of this…
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…
We present new bulge stellar velocity dispersion measurements for 10 active galaxies with secure $M_{BH}$ determinations from reverberation-mapping. These new velocity dispersion measurements are based on spatially resolved kinematics from…
The structure and kinematics of the old component of the Galactic bulge are still a matter of debate. The bulk of the bulge as traced by red clump stars includes two main components, which are usually identified as the metal-rich and…