相关论文: A near zero velocity dispersion stellar component …
We present Keck/DEIMOS spectroscopy of stars in 8 of the newly discovered ultra-faint dwarf galaxies around the Milky Way. We measure the velocity dispersions of Canes Venatici I and II, Ursa Major I and II, Coma Berenices, Hercules, Leo IV…
We determined the spatial structure of the scattered concentration of galaxies in the Canes Venatici constellation. We redefined the distances for 30 galaxies of this region using the deep images from the Hubble Space Telescope archive with…
We present low-resolution spectroscopy of 120 red giants in the Galactic satellite dwarf spheroidal (dSph) Leo I, obtained with the GeminiN-GMOS and Keck-DEIMOS spectrographs. We find stars with velocities consistent with membership of Leo…
VV124 (UGC 4879) is an isolated, dwarf irregular/dwarf spheroidal (dIrr/dSph) transition-type galaxy at a distance of 1.36 Mpc. Previous low-resolution spectroscopy yielded inconsistent radial velocities for different components of the…
We present new chemo--kinematics of the Hercules dwarf galaxy based on Keck II-- DEIMOS spectroscopy. Our 21 confirmed members have a systemic velocity of $v_{\mathrm{Herc}}=46.4\pm1.3$ kms$^{-1}$ and a velocity dispersion…
As part of a radial velocity survey of low Galactic latitude structures that we undertook with the 2dF spectrograph on the AAT, we present the radial velocities of more than 1500 Red Giant Branch and Red Clump stars towards the centre of…
We present metallicity and radial velocity for 450 bonafide members of the Sagittarius dwarf spheroidal (Sgr dSph) galaxy, measured from high resolution (R~18000) FLAMES@VLT spectra. The targets were carefully selected (a) to sample the…
We develop, implement and characterise an enhanced data reduction approach which delivers precise, accurate, radial velocities from moderate resolution spectroscopy with the fibre-fed VLT/FLAMES+GIRAFFE facility. This facility, with…
We present new spectroscopic data for twenty six stars in the recently-discovered Canes Venatici I (CVnI) dwarf spheroidal galaxy. We use these data to investigate the recent claim of the presence of two dynamically inconsistent stellar…
We present the first deep color-magnitude diagram of the Canes Venatici I (CVnI) dwarf galaxy from observations with the wide field Large Binocular Camera on the Large Binocular Telescope. Reaching down to the main-sequence turnoff of the…
We present the projected velocity dispersion profile for the remote (d=233kpc) Galactic dwarf spheroidal (dSph) galaxy Leo II, based on 171 discrete stellar radial velocities that were obtained from medium-resolution spectroscopy using the…
The aim of this work is to find a progenitor for Canes Venatici I (CVn I), under the assumption that it is a dark matter free object that is undergoing tidal disruption. With a simple point mass integrator, we searched for an orbit for this…
We present new FLAMES$+$GIRAFFE spectroscopy of 36 member stars in the isolated Local Group dwarf spheroidal galaxy Tucana. We measure a systemic velocity for the system of $v_{\mathrm{Tuc}}=216.7_{-2.8}^{+2.9}$kms$^{-1}$, and a velocity…
We show that measured velocity dispersions of dwarf spheroidal galaxies from about 4 to 10 km/s are unlikely to be inflated by more than 20% due to the orbital motion of binary stars, and demonstrate that the intrinsic velocity dispersions…
We present a new suite of photometric and spectroscopic data for the faint Bootes II dwarf spheroidal galaxy candidate. Our deep photometry, obtained with the INT/WFC, suggests a distance of 46 kpc and a small half-light radius of 4.0…
We present radial velocities and [Fe/H] abundances for 340 stars in the Fornax dwarf spheroidal from R~16,000 spectra. The targets have been obtained in the outer parts of the galaxy, a region which has been poorly studied before. Our…
Photometry alone is not sufficient to unambiguously distinguish between ultra-faint star clusters and dwarf galaxies because of their overlap in morphological properties. Here we report on VLT/GIRAFFE spectra of candidate member stars in…
We present new radial velocity results for 176 stars in the Fornax dwarf spheroidal galaxy, of which at least 156 are probable Fornax members. We combine with previously published data to obtain a radial velocity sample with 206 stars, of…
We present stellar radial velocity data for the Draco dwarf spheroidal galaxy obtained using the AF2/WYFFOS instrument combination on the William Herschel Telescope. Our dataset consists of 186 member stars, 159 of which have good quality…
We investigate the spatial distribution, kinematics, and metallicity of stars in the Draco dwarf spheroidal galaxy using data from the Dark Energy Spectroscopic Instrument (DESI). We identify 155 high probability members of Draco using line…