相关论文: Andromeda and its satellites - a kinematic perspec…

We report here the discovery of an apparent excess of 2MASS M giant candidates with dereddened 0.85 < J-K_S < 1.2 spanning a considerably large area of the celestial sphere between, at least, $100\degr < l < 150\degr$ and $-20\degr > b >…

We present a dynamical measurement of the tangential motion of the Andromeda system, the ensemble consisting of the Andromeda Galaxy (M31) and its satellites. The system is modelled as a structure with cosmologically-motivated velocity…

With a central surface brightness of $\mu_0=29.3$ mag. per sq. arcsec, and half-light radius of $r_{\rm half}=3.1^{+0.9}_{-1.1}$~kpc, Andromeda XIX (And XIX) is an extremely diffuse satellite of Andromeda. We present spectra for $\sim100$…

We report the discovery of a new dwarf spheroidal galaxy near M31 based on INT/WFC imaging. The system, Andromeda XVII (And XVII), is located at a projected radius of ~44 kpc from M31 and has a line-of-sight distance of 794+/-40 kpc…

We estimate the systemic orbital kinematics of the Milky Way classical satellites and compare them with predictions from the \Lambda{} cold dark matter (\Lambda{}CDM) model derived from a semi-analytical galaxy formation model applied to…

Many of the satellites of galactic-mass systems such as the Miky Way, Andromeda and Centaurus A show evidence of coherent motions to a larger extent than most of the systems predicted by the standard cosmological model. It is an open…

The Andromeda Galaxy (M31) is one of a few galaxies that has sufficient angular size on the sky to be resolved by the Planck satellite. Planck has detected M31 in all of its frequency bands, and has mapped out the dust emission with the…

The Andromeda (M31) and Triangulum (M33) galaxies are the closest Local Group galaxies to the Milky Way, being only 785 and 870 kpc away. These two galaxies provide an independent view of high-energy processes that are often obscured in our…

The distribution of smaller satellite galaxies around large central galaxies has attracted attention because peculiar spatial and kinematic configurations have been detected in some systems. A particularly striking example of such behavior…

We present Keck II/DEIMOS spectroscopy of the three distant dwarf galaxies of M31 Lacerta I, Cassiopeia III, and Perseus I, recently discovered within the Pan-STARRS1 3\pi imaging survey. The systemic velocities of the three systems…

Recent work has shown that both the Milky Way and the Andromeda galaxies possess the unexpected property that their dwarf satellite galaxies are aligned in thin and kinematically coherent planar structures. It is now important to evaluate…

We report on the discovery of three new dwarf galaxies in the Local Group. These galaxies are found in new CFHT/MegaPrime g,i imaging of the south-western quadrant of M31, extending our extant survey area to include the majority of the…

We report the discovery of a new dwarf galaxy, Andromeda XXVIII, using data from the recently-released SDSS DR8. The galaxy is a likely satellite of Andromeda, and, at a separation of $365^{+17}_{-1}$ kpc, would be one of the most distant…

We measure the intrinsic shapes and alignments of the dwarf spheroidal (dSph) galaxies of the Local Group. We find the dSphs of the Milky Way are intrinsically flatter (mean intrinsic ellipticity $\mu_E\sim0.6$) than those of M31…

The Great Andromeda Galaxy (M31) is the nexus of the near-far galaxy evolution connection and a principal data point for near-field cosmology. Due to its proximity (780 kpc), M31 can be resolved into individual stars like the Milky Way…

We present a spectroscopic survey of the giant stellar stream found in the halo of the Andromeda galaxy. Taken with the DEIMOS multi-object spectrograph on the Keck2 telescope, these data display a narrow velocity dispersion of 11+/-3 km/s,…

We have explored the hypothesis that the total mass-ratio of the two main galaxies of the Local Group: Andromeda Galaxy(M31) and the Milky Way (MW) can be constrained measuring the tidal force induced by the surrounding mass distribution,…

We present the results of a kinematic survey of the dwarf spheroidal satellite of M31, And-IX, which appears to be the lowest surface brightness and also the faintest galaxy (M_V = -8.3) found to date. Using Keck/DEIMOS spectroscopic data,…

Tidal streams from existing and destroyed satellite galaxies populate the outer regions of the Andromeda galaxy (M31). This inhomogeneous debris can be studied without many of the obstacles that plague Milky Way research. We review the…

(abridged) The Milky Way (MW) and Andromeda (M31) galaxies possess rotating planes of satellites. Their formation has not been explained satisfactorily yet. It was suggested that the MW and M31 satellites are ancient tidal dwarf galaxies,…