相关论文: Three-dimensional structure of the Sagittarius dSp…
We present a detailed study of the internal structure and kinematics of the core of the Sagittarius dwarf spheroidal galaxy (Sgr). Using machine-learning techniques, we have combined the information provided by 3300 RR Lyrae stars, more…
We report the detection of $\sim$ 1500 RR Lyrae of Bailey type ab located in the Sagittarius dwarf galaxy (Sgr). These variables have been detected on two ESO Schmidt fields centred on (l,b)=(3.1 deg,-7.1 deg) and (6.6 deg, -10.8 deg),…
We derive the distance to the northern extension of the Sagittarius (Sgr) dwarf spheroidal galaxy from 203 Sgr RR0 Lyrae stars found in the MACHO database. Their distances are determined differentially with respect to 288 Galactic Bulge RR0…
Using Gaia DR3 data, we examine the kinematics of the central core of the Sagittarius (Sgr) dwarf spheroidal galaxy using data which includes proper motions and line-of-sight velocities for member stars in addition to their projected…
We use the astrometric and photometric data from Gaia Data Release 2 and line-of-sight velocities from various other surveys to study the 3d structure and kinematics of the Sagittarius dwarf galaxy. The combination of photometric and…
We present a comprehensive and precise description of the Sagittarius (Sgr) stellar stream's 3D geometry as traced by its old stellar population. This analysis draws on the sample of ${\sim}44,000$ RR Lyrae (RRab) stars from the Pan-STARRS1…
The Sagittarius galaxy (Sgr), the closest satellite galaxy of the Milky Way, has survived for many orbits about the Galaxy. Extant numerical calculations modeled this galaxy as a system with a centrally-concentrated mass profile, following…
We discuss the density and radial velocity distributions of over 3000 candidate RR Lyrae stars selected by various methods using Sloan Digital Sky Survey data for about 1000 deg^2 of sky. This is more than 20 times larger sample than…
We use the $Gaia$ DR2 RR Lyrae sample to gain an uninterrupted view of the Galactic stellar halo. We dissect the available volume in slices parallel to the Milky Way's disc to show that within $\sim30$ kpc from the Galactic centre the halo…
The Sagittarius dwarf spheroidal galaxy provides us with the unique opportunity to study an ongoing Galactic cannibalistic event between our Milky Way Galaxy and a satellite dwarf galaxy. Understanding this event crucially requires…
We report the discovery of 30 type a,b RR Lyrae (RRab) which are likely members of the Sagittarius (Sgr) dwarf galaxy. Accurate positions, periods, amplitudes and magnitudes are presented. Their distances are determined with respect to RRab…
We present a search for RR Lyrae variable stars from archival observations of the Southern Edgeworth-Kuiper Belt Object survey. The survey covers 1675 square degrees along the ecliptic to a mean depth of V=19.5, i.e. a heliocentric distance…
We present a new N-body model for the tidal disruption of the Sagittarius (Sgr) dwarf that is capable of simultaneously satisfying the majority of angular position, distance, and radial velocity constraints imposed by current wide-field…
The Sagittarius stream is one of the best tools that we currently have to estimate the mass and shape of our Galaxy. However, assigning membership and obtaining the phase-space distribution of the stars that form the tails is quite…
We present an analysis of Galactic halo structure and substructure traced by ~500 RR Lyrae stars in the SDSS stripe 82 region. The main result of this study is a 2D map of the Galactic halo that reaches distances of 100 kpc and traces…
We have discovered a new Galactic satellite galaxy in the constellation of Sagittarius. The Sagittarius dwarf galaxy is the nearest galaxy known, subtends an angle of $> 10$ degrees on the sky, lies at a distance of $24 \kpc$ from the Sun,…
M giants selected from the Two Micron All Sky Survey (2MASS) have been used to trace streams of tidal debris apparently associated with the Sagittarius dwarf spheroidal galaxy (Sgr) that entirely encircle the Galaxy. While the Sgr M giants…
Observations of the lengthy tidal streams produced by the destruction of the Sagittarius dwarf spheroidal (Sgr dSph) are capable of providing strong constraints on the shape of the Galactic gravitational potential. However, previous work,…
We have assembled a large-area spectroscopic survey of giant stars in the Sagittarius (Sgr) dwarf galaxy core. Using medium resolution (R ~15,000), multifiber spectroscopy we have measured velocities of these stars, which extend up to 12…
The Sagittarius (Sgr) dwarf spheroidal galaxy is one of the most prominent satellites of the Milky Way (MW). It is currently undergoing tidal disruption, forming an extensive stellar stream that provides key insights into the assembly…