Related papers: The Stellar Content of Galaxy Halos: A Comparison …
The outer regions of galaxies are expected to contain important clues about the way in which galaxies are assembled. Although quantitative study of these parts has been severely limited in the past, breakthroughs are now being made thanks…
(Abridged) We performed the spectroscopic observations of 11 confirmed GCs in M31 with the Xinglong 2.16m telescope and we mainly focus on the fits method and the metallicity gradient for the M31 GC sample. We analyzed and discussed more…
We present a study of spatial variations in the metallicity of old red giant branch stars in the Andromeda galaxy. Photometric metallicity estimates are derived by interpolating isochrones for over seven million stars in the Panchromatic…
Recent work has shown that Milky Way-mass galaxies display an incredible range of stellar halo properties, yet the origin of this diversity is unclear. The nearby galaxy M81 $-$ currently interacting with M82 and NGC 3077 $-$ sheds unique…
We derive a star catalogue generated from the images taken as part of the 37.5 sq. deg Millennium Galaxy Catalogue. These data, alone and together with colours gained from the Sloan Digital Sky Survey Early Data Release, allow the analysis…
As part of our survey of galactic stellar halos, we investigate the structure and stellar populations of the northern outer part of the stellar halo in NGC55, a member galaxy of the Sculptor Group, using deep and wide-field V- and I-band…
(Abridged) This paper presents the first connections made between two local features in velocity-space found in a survey of M giant stars and stellar spatial inhomogeneities on global scales. Comparison to cosmological, chemodynamical…
The halo of M31 shows a wealth of substructures that are consistent with satellite accretion. Here we report on kinematic and abundance results from Keck/DEIMOS spectroscopy in the calcium triplet region of over 3500 red giant star…
We present chemical abundances of red giant branch (RGB) stars in the dwarf spheroidal (dSph) satellite system of Andromeda (M31), using spectral synthesis of medium resolution (R $\sim 6000$) spectra obtained with the Keck II telescope and…
We present a resolved-star spectroscopic survey of 15 dwarf spheroidal (dSph) satellites of the Andromeda Galaxy (M31) as part of the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH) project. We filter foreground…
As part of the Z-PAndAS Keck II DEIMOS survey of resolved stars in our neighboring galaxy, Andromeda (M31), we have built up a unique data set of measured velocities and chemistries for thousands of stars in the Andromeda stellar halo,…
Published maps of red giant stars in the halo region of M31 exhibit a giant stellar stream to the south of this galaxy, as well as a giant "shelf" to the northeast of M31's center. Using these maps, we find that there is a fainter shelf of…
We present wide and deep photometry of the northwest part of the halo of the Andromeda galaxy (M31) using Hyper Suprime-Cam on the Subaru Telescope. The survey covers 9.2 deg$^{2}$ field in the $g$, $i$, and $NB515$ bands and shows a clear…
Various theoretical models predict the existence of extended $\gamma$-ray halo around normal galaxies that could be produced by interactions of cosmic rays with the circumgalactic medium or by annihilation or decay of hypothetical dark…
The optical properties of the second generation dust that we observe in debris disks remain quite elusive, whether it is the absorption efficiencies at millimeter wavelengths or the (un)polarized phase function at near-infrared wavelengths.…
We use deep surface photometry of the giant elliptical M49 (NGC 4472), obtained as part of our survey for diffuse light in the Virgo Cluster, to study the stellar populations in its outer halo. Our data trace M49's stellar halo out to ~ 100…
M31 hosts a rich population of outer halo ($R_{\rm{proj}} > 25$ kpc) globular clusters (GCs), many of which show strong evidence for spatial and/or kinematical associations with large-scale tidal debris features. We present deep Hubble…
The subsequent coalescence of low--mass halos over cosmic time is thought to be the major formation channel of massive spiral galaxies like the Milky Way and the Andromeda Galaxy (M31). The gaseous halo of a massive galaxy is considered to…
We use the Illustris Simulations to gain insight into the build-up of the outer, low-surface brightness regions which surround galaxies. We characterize the stellar haloes by means of the logarithmic slope of the spherically-averaged…
The detection of planar structures within the satellite systems of both the Milky Way (MW) and Andromeda (M31) has been reported as being in stark contradiction to the predictions of the standard cosmological model ($\Lambda$CDM). Given the…