Related papers: Population Gradients in Local Group Dwarf Spheroid…
In this article we investigate the morphology and stellar populations of high-redshift galaxies through multi-waveband HST imaging and ground-based spatially-resolved spectroscopy. We study the redshift evolution of galaxy morphology in the…
We report the discovery of a sizeable, previously unknown variable star population in the Sagittarius dwarf spheroidal globular clusters NGC 5634, Arp 2 and Terzan 8. Location, preliminary pulsation periods and B-band light curves in…
We use orbit based dynamical models to fit the 2nd and 4th moments of the line of sight velocity distributions of the Fornax, Sculptor, Carina and Sextans dwarf spheroidal galaxies. Our goal is to compare dark matter profile models of these…
Numerical models of the tidal disruption of the Sagittarius (Sgr) dwarf galaxy have recently been developed that for the first time simultaneously satisfy most observational constraints on the angular position, distance, and radial velocity…
We report the discovery of NGC 253-dw2, a dwarf spheroidal (dSph) galaxy candidate undergoing tidal disruption around a nearby spiral galaxy, NGC 253 in the Sculptor group: the first such event identified beyond the Local Group. The dwarf…
We present an analysis of the kinematics of 14 satellites of the Milky Way (MW). We use proper motions (PMs) from the $Gaia$ Early Data Release 3 (EDR3) and line-of-sight velocities ($v_{\mathrm{los}}$) available in the literature to derive…
We present a study on the radial profiles of D4000,luminosity-weighted stellar ages $\tau_L$,and luminosity-weighted stellar metallicities $[Z/H]_L$ of 3654 nearby galaxies($0.01<z<0.15$)using the IFU spectroscopic data from the MaNGA…
In this contribution initial results from colour-magnitude diagrams for five dEs in the M81 group are presented. The colour-magnitude diagrams, derived from HST/ACS images, reach well below the red giant branch tip and allow evaluation of…
We present V, I photometry of the Sagittarius Dwarf Spheroidal galaxy (Sgr) for a region of ~ 1^{circ} times 1^{circ}, centered on the globular cluster M 54. This catalog is the largest database of stars (~500,000) ever obtained for this…
We present new measurements of central line-strength indices (namely Mg2, <Fe>, and Hbeta and gradients for a sample of 6 bright spheroidal galaxies (Sph's) in the Virgo cluster. Comparison with similar measurements for elliptical galaxies…
As part of an ongoing search for dwarf elliptical galaxies (dE) in the vicinity of the Local Group, we acquired deep B and R-band images for five dE candidates identified in the Sculptor (Scl) group region. We carried out a surface…
We present a deep near-infrared color--magnitude diagram of the Galactic globular cluster 47 Tucanae, obtained with the Visible and Infrared Survey Telescope for Astronomy (VISTA) as part of the VISTA near-infrared Y, J, K_s survey of the…
I analyze the properties of the first galaxies in cosmological simulations with radiative feedback. Preliminary results indicate similarities with the observed properties of the bulk of dwarf spheroidal galaxies (dSphs) in the Local Group…
The study of dwarf galaxies in groups is a powerful tool for investigating galaxy evolution, chemical enrichment and environmental effects on these objects. Here we present results obtained for dwarf galaxies in the Centaurus A complex, a…
(Abridged) We present deep, sub-horizontal branch, multi-colour photometry of the Andromeda II dwarf spheroidal (And II dSph) taken with Subaru Suprime-Cam. We identify a red clump population in this galaxy, the first time this feature has…
We present the spatially resolved star formation history (SFH) of the Carina dwarf spheroidal galaxy, obtained from deep, wide-field g,r imaging and a metallicity distribution from the literature. Our photometry covers $\sim2$ deg$^2$,…
Hubble Space Telescope WFPC2 images of the Local Group dwarf galaxy Tucana reveal an unbiased sample of distant field galaxies. While a large number of these galaxies can be classified according to standard Hubble types, a significant…
From R-band images of 42 Hickson compact groups, we present a sample of 47 candidate dwarf galaxies that are associated with the tidal tails and arms in the groups. The candidates, found in 15 tidal features, have R magnitudes and masses…
The question of the existence of active tidal disruption around various dSph galaxies remains controversial. That debate often centers on the nature (bound vs. unbound) of extended populations of stars. However, the more fundamental issue…
We study the resolved stellar populations of dwarf galaxies in the nearby Centaurus A/M83 group of galaxies. Our goal is to characterize their evolutionary history and to investigate eventual similarities or differences with the dwarf…