相关论文: Detection of a population gradient in the Sagittar…
We report on the recovery of a Blue Horizontal Branch (BHB) population belonging to the Sagittarius Dwarf Spheroidal Galaxy (Sgr). The sequence is clearly identified in the (V, V-I) Color Magnitude Diagram (CMD) obtained for about 500,000…
We use a sample of blue horizontal branch (BHB) stars from the Sloan Digital Sky Survey Data Release 7 to explore the structure of the tidal tails from the Sagittarius Dwarf Galaxy. We use a method yielding BHB star candidates with up to…
We present 2-degree field spectroscopic observations of a sample of 96 A-type stars selected from the Sloan Digital Sky Survey Data Release 3 (SDSS DR3). Our aim is to identify blue horizontal branch (BHB) stars in order to measure the…
We have selelcted 556 Red Horizontal Branch (RHB) stars along the streams of the Sagittarius dwarf galaxy (Sgr) from SDSS DR7 spectroscopic data using a theoretical model. The metallicity and \alpha-elements distributions are investigated…
The structure of the Sagittarius stream in the Southern Galactic hemisphere is analysed with the Sloan Digital Sky Survey Data Release 8. Parallel to the Sagittarius tidal track, but ~ 10deg away, there is another fainter and more…
We have probed a section (l ~ 150, b ~ -60) of the trailing tidal arm of the Sagittarius dwarf spheroidal galaxy by identifying a sample of Red Clump stream stars. Red Clump stars are not generally found in the halo field, but are found in…
We trace the tidal Stream of the Sagittarius dwarf spheroidal galaxy (Sgr dSph) using Red Clump stars from the catalog of the Sloan Digital Sky Survey - Data Release 6, in the range 150{\deg} < RA < 220{\deg}, corresponding to the range of…
Context. The Sagittarius (Sgr) dwarf spheroidal galaxy is currently being disrupted under the strain of the Milky Way. A reliable reconstruction of Sgr star formation history can only be obtained by combining core and stream information.…
The main aim of this paper is to report two new detections of tidal debris in the northern stream of the Sagittarius dwarf galaxy located at 45 arcdeg and 55 arcdeg from the center of galaxy. Our observational approach is based on deep…
We present the first detailed quantitative study of the stellar populations of the Sagittarius (Sgr) streams within the Stripe 82 region, using photometric and spectroscopic observations from the Sloan Digital Sky Survey (SDSS). The star…
We show that the Sagittarius dwarf tidal stream can be traced with very red K/M-giant stars selected from SDSS photometry. A subset of these stars are spectroscopically confirmed with SEGUE and SDSS spectra, and the distance scale of 2MASS…
We constructed a sample of 13,798 stars with $T\rm_{eff}$, log $g$, [Fe/H], radial velocity, proper motions and parallaxes from LAMOST DR5 and Gaia DR2 in the LAMOST Complete Spectroscopic Survey of Pointing Area (LaCoSSPAr) at the Southern…
The stellar stream connected to the Sagittarius (Sgr) dwarf galaxy is the most massive tidal stream that has been mapped in the Galaxy, and is the dominant contributor to the outer stellar halo of the Milky Way. We present metallicity maps…
In this work, we study the phase-space and chemical properties of Sagittarius (Sgr) stream, the tidal tails produced by the ongoing destruction of Sgr dwarf spheroidal (dSph) galaxy, focusing on its very metal-poor (VMP; $\rm[Fe/H] < -2$)…
We present the deep and wide $V$ and $I_c$ photometry of the Sextans dwarf spheroidal galaxy (dSph) taken by Suprime-Cam imager on the Subaru Telescope, which extends out to the tidal radius. The colour-magnitude diagram (CMD) reaches two…
We characterize the kinematic and chemical properties of $\sim$3,000 Sagittarius (Sgr) stream stars, including K-giants, M-giants, and BHBs, select from SEGUE-2, LAMOST, and SDSS separately in Integrals-of-Motion space. The orbit of Sgr…
Providing a detailed picture of the Sagittarius (Sgr) stream offers important constraints on the build-up of the Galactic halo as well as its gravitational potential at large radii. While several attempts have been made to model the…
We present abundances of C, O, Ti, and Fe for eleven M-giant stars in the trailing tidal arm of the Sagittarius dwarf (Sgr). The abundances were derived by comparing synthetic spectra with high-resolution infrared spectra obtained with the…
We present first results of a large photometric survey devoted to study the star formation history of the Sagittarius dwarf spheroidal galaxy (Sgr dSph). Three wide strips (9 X 35 arcmin^2) located at l~5 and b=-16, -14, -12 have been…
The Sagittarius dwarf spheroidal (Sgr) is a dissolving galaxy being tidally disrupted by the Milky Way (MW). Its stellar stream still poses serious modelling challenges, which hinders our ability to use it effectively as a probe of the MW…