相关论文: Are Complex A and the Orphan Stream related?

We report the serendipitous discovery of a stellar stream in the constellation Pegasus in the south Galactic hemisphere. The stellar stream was detected using the SDSS Data Release 14 by means of a matched filter in the color--magnitude…

We report on the detection in Sloan Digital Sky Survey data of a 63 degree-long tidal stream of stars, extending from Ursa Major to Cancer. The stream has no obvious association with the orbit of any known cluster or galaxy. The contrast of…

During the past 20 years, numerous stellar streams have been discovered in both the Milky Way and the Local Group. These streams have been tidally torn from orbiting systems, which suggests that most of them should roughly trace the orbit…

The stellar velocity fields of elliptical galaxies hold clues to their dynamical structure and origin. The construction of velocity field models is greatly simplified by assuming an approximate geometrical form for the streamlines of the…

The wide-field CCD camera at the CFH telescope was used to survey the giant stellar stream in the Andromeda galaxy, resolving stars down the red giant branch in M31 to I ~ 25, a magnitude deeper than our previous INT survey of this galaxy…

We present radial velocities for five member stars of the recently discovered young (age= 100-150 Myr) stellar system Price-Whelan 1 (PW 1), that is located far away in the Galactic Halo (D~ 29 kpc, Z~ 15 kpc), and that is probably…

Hydro cosmological simulations reveal that massive galaxies at high redshift are fed by long narrow streams of merging galaxies and a smoother component of cold gas. We post-process seven high-resolution simulated galaxies with radiative…

When a massive object crosses a star stream velocity changes are induced both along and transverse to the stream which can lead to the development of a visible gap. For a stream narrow relative to its orbital radius the time of stream…

In this contribution we discuss the expected properties of our halo if our Galaxy had been built from mergers of smaller systems. Using both analytic arguments and high-resolution simulations, we find that the Galactic halo in the Solar…

Spectroscopy for faint dwarf galaxies outside of our own Local Group is challenging. Here, we present MUSE spectroscopy to study the properties of four known dwarf satellites and one stellar stream (KK208) surrounding the nearby grand…

We have mapped two regions at the northern tip of the Magellanic Stream in neutral hydrogen 21-cm emission using the Arecibo telescope. The new data are used to study the morphology and properties of the Stream far away from the Magellanic…

The study of dynamically cold stellar streams reveals information about the gravitational potential where they reside and provides important constraints on dark matter properties. However, their intrinsic faintness makes detection beyond…

The gravitational field of a massive object (for instance, of a galaxy group or cluster) disturbs the Hubble stream, decreasing its speed. Dependence $v(r_0)$ of the radial velocity of the stream from the present-day radius $r_0$ can be…

Thin halo star streams originate from the evaporation of globular clusters and therefore provide information about the early epoch globular cluster population. The observed tidal tails from halo globular clusters in the Milky Way are much…

We present the discovery of a large population of stellar streams that surround the inner Galaxy, found in the Gaia DR2 catalog using the new STREAMFINDER algorithm. Here we focus on the properties of eight new high-significance structures…

We investigate numerically the interaction of a stream of granular particles with a resting obstacle in two dimensions. For the case of high stream velocity we find that the force acting on the obstacle is proportional to the square of the…

Parkes neutral hydrogen 21 cm line (HI) observations of the surroundings of 9 early-type Local Group dwarfs are presented. We detected numerous HI clouds in the general direction of those dwarfs and these clouds are often offset from the…

The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the…

We present a data-driven method for reconstructing the galactic acceleration field from phase-space measurements of stellar streams. Our approach is based on a flexible and differentiable fit to the stream in phase-space, enabling a direct…

Searching the HI Parkes All-Sky Survey (HIPASS) and its northern extension, we detected a population of very compact high-velocity clouds (HVCs) with similar velocities in the Galactic standard-of-rest frame which appear to be arranged in…