相关论文: Comparing bulge RR Lyrae stars with bulge giants -…

Context. Observational evidence has accumulated in the past years, showing that the Galactic bulge includes two populations, a metal poor and a metal rich one that, in addition to a different metallicity, show different alpha over iron…

We have analyzed a sample of 27,258 fundamental-mode RR Lyrae variable stars (type RRab) detected recently toward the Galactic bulge by the Optical Gravitational Lensing Experiment (OGLE) survey. The data support our earlier claim that…

We analyze the kinematics and spatial distribution of 15,599 fundamental-mode RR Lyrae (RRL) stars in the Milky Way bulge by combining OGLE-IV photometric data and Gaia DR2 proper motions. We show that the longitudinal proper motions and…

RR Lyrae stars are excellent tracers of stellar populations for old, metal-poor components in the Milky Way Galaxy and the Local Group. Their luminosities have a metallicity-dependence, but determining spectroscopic [Fe/H] metallicities for…

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…

We have combined optical and near-infrared data of known RR Lyrae (RRL) stars in the bulge in order to study the spatial distribution of its metal-poor component by measuring precise reddening values and distances of 7663 fundamental-mode…

We have used photometric data on almost 91 000 fundamental-mode RR Lyrae stars (type RRab) detected by the OGLE survey to investigate properties of old populations in the Milky Way. Based on their metallicity distributions, we demonstrate…

We present an analysis of the structure, kinematics, and chemo-dynamical properties of the Milky Way bulge using RR Lyrae stars from OGLE, and giant stars from APOGEE and Gaia that have distances placing them in the inner Galaxy. Firstly,…

Radial velocities of fifteen double-mode bulge RR Lyrae (RR01) stars are presented, six of which belong to a compact group of RR01 stars in pulsation space, with the ratio of first-overtone period to fundamental-mode period,…

RR Lyrae stars in the bulge have been reported to be associated with the spheroidal, relatively metal-poor component. They offer a way to trace this component with precise distances. While a few studies of RR Lyrae spectra with medium/high…

RR Lyrae stars being distance indicators and tracers of old population serve as excellent probes of the structure, formation, and evolution of our Galaxy. Thousands of them are being discovered in ongoing wide-field surveys. The OGLE…

The VISTA Variables in the V\'ia L\'actea (VVV) is a near-IR time-domain survey of the Galactic bulge and southern plane. One of the main goals of this survey is to reveal the 3D structure of the Milky Way through their variable stars.…

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…

We have analyzed the data on 16,836 RR Lyrae (RR Lyr) variables observed toward the Galactic bulge during the third phase of the Optical Gravitational Lensing Experiment (OGLE-III), which took place in 2001-2009. Using these standard…

We present 947 radial velocities of RR Lyrae variable stars in four fields located toward the Galactic bulge, observed within the data from the ongoing Bulge RR Lyrae Radial Velocity Assay (BRAVA-RR). We show that these RR Lyrae stars…

RR Lyrae stars in the Milky Way are good tracers to study the kinematic behaviour and spatial distribution of older stellar populations. A recently established well documented sample of 217 RR Lyr stars with V<12.5 mag, has been used to…

We present a kinematical study of RR~Lyrae stars associated with two Oosterhoff groups in the Galactic bulge. We used data published in the first paper of the series, plus proper motions from the {\it Gaia} Data Release 2, and radial…

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…

RR Lyrae stars have long been considered reliable tracers of old, metal-poor populations, primarily due to their prevalence in globular clusters and the Galactic halo. However, the discovery of a metal-rich subpopulation in the Galactic…

Data of our compiled catalog containing the positions, velocities, and metallicities of 415 RR~Lyrae variable stars and the relative abundances [el/Fe] of 12~elements for 101 RR~Lyrae stars, including four $\alpha$~elements (Mg, Ca, Si, and…