相关论文: Hints of a disrupted binary dwarf galaxy in the Sa…

In numerous studies of the outer Galactic halo some evidence for accretion has been found. If the outer halo did form in part or wholly through merger events, we might expect to find coherent streams of stars and globular clusters following…

The Sloan Digital Sky Survey has recently discovered a coherent ring of stars at low galactic latitude that is believed to be the tidal stream of a merging dwarf galaxy in the Galactic plane (named the Monoceros tidal stream). The existence…

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 investigate the origin of NGC 5634 through a comprehensive analysis of its morphology, kinematics and dynamics. Utilizing data from the DESI Legacy Survey, we refined its fundamental parameters (age t = 12.8 +/- 0.3 Gyr, metallicity…

Binary stellar systems form a large fraction of the Galaxy's stars. They are useful as laboratories for studying the physical processes taking place within stars, and must be correctly taken into account when observations of stars are used…

The recently discovered Virgo stellar over-density, which expands over \~1000deg^2 perpendicularly to the Galactic disk plane (7< Z <15 kpc, R~7 kpc), is the largest clump of tidal debris ever detected in the outer halo and is likely…

Hypervelocity stars (HVSs) are valuable tracers of extreme dynamical processes. The Sagittarius dwarf spheroidal galaxy (Sgr dSph), currently undergoing tidal disruption, offers a unique environment to search for such stars. We aim to…

The photometric study of the Sagittarius dwarf galaxy by Marconi et al (1998) has suggested the presence of a spread in metallicity (-0.7< [Fe/H] < -1.6), which may result from different bursts of star formation. We present the results from…

The recently discovered Indus stellar stream exhibits a diverse chemical signature compared to what is found for most other streams due to the abundances of two outlier stars, Indus$\_$0 and Indus$\_$13. Indus$\_$13, exhibits an extreme…

We have derived from VIMOS spectroscopy the radial velocities for a sample of 71 stars selected from CFHT/Megacam photometry around the Galactic globular cluster NGC7492. In the resulting velocity distribution, it is possible to distinguish…

We explore the connection between the gravitational wave (GW) merger rates of stellar-mass binary black holes (BBH) and galaxy properties. We do this by generating populations of stars using the binary population synthesis code COMPAS and…

We present tentative evidence for the existence of a dissolved star cluster at [Fe/H]=-2.7 in the Sextans dwarf spheroidal galaxy. We use the technique of chemical tagging to identify stars that are highly clustered in a multi-dimensional…

M54 is the central cluster of the Sagittarius dwarf galaxy. This stellar system is now in process of being disrupted by the tidal interaction with the Milky Way and represents one of the building blocks of the Galactic Halo. Recent…

The White Dwarf Binary Pathways Survey aims at increasing the number of known detached A, F, G and K main sequence stars in close orbits with white dwarf companions (WD+AFGK binaries) to refine our understanding about compact binary…

It has been recently claimed that the confined structure of the debris from the Sagittarius dwarf implies that the dark-matter halo of our Galaxy should be nearly spherical, in strong contrast with predictions from cold dark-matter (CDM)…

We explore a newly proposed channel to create binary black holes of stellar origin. This scenario applies to massive, tight binaries where mixing induced by rotation and tides transports the products of hydrogen burning throughout the…

In this work we present two new $\sim10^9$ particle self-consistent simulations of the merger of a Sagittarius-like dwarf galaxy with a Milky Way-like disc galaxy. One model is a violent merger creating a thick disc, and a…

We investigate the formation processes of the Galactic globular cluster (GC) omega Cen with multiple stellar populations based on our original hydrodynamical simulations with chemical enrichment by Type II supernovae (SNe II), asymptotic…

The origins of most stellar streams in the Milky Way are unknown. With improved proper motions provided by Gaia EDR3, we show that the orbits of 23 Galactic stellar streams are highly clustered in orbital phase space. Based on their…

The tidal disruption of the Sagittarius dwarf Spheroidal galaxy (Sgr dSph) is producing the most prominent substructure in the Milky Way (MW) halo, the Sagittarius Stream. Aside from field stars, the Sgr dSph is suspected to have lost a…