Related papers: Morphological Evolution of Dwarf Galaxies in the L…
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…
We perform collisionless N-body simulations to investigate whether binary mergers between rotationally-supported dwarfs can lead to the formation of dwarf spheroidal galaxies (dSphs). Our simulation campaign is based on a hybrid approach…
Dwarf spheroidal galaxies are the most dark matter dominated systems in the nearby Universe and their origin is one of the outstanding puzzles of how galaxies form. Dwarf spheroidals are poor in gas and stars, making them unusually faint,…
Recent N-Body simulations have shown that dIrrs evolve into dSphs owing to the strong tidal perturbation of the Milky Way. Satellites whose dark matter halos have a core or an NFW profile with a concentration $c < 5$ undergo severe…
The morphological types of 5840 galaxies were classified by a visual inspection of color images using the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) to produce a morphology catalog of a representative sample of local galaxies with…
There appears to exist a conflict between the standard structure formation theory and the existence of the faint dwarf spheroidal galaxies in the Local Group. Theoretical considerations suggest that a cold dark matter universe has been a…
Different structural parameter correlations show how classical bulge components and elliptical galaxies are different from spiral and S0 galaxy disks, irregular (Im) galaxies, and spheroidal (Sph) galaxies. In contrast, the latter,…
We consider an all-sky sample of 1029 Local Volume (LV) galaxies situated within a distance of 11 Mpc. Their majority have precise distances, estimates of hydrogen mass fraction and star-formation rate derived from far-ultraviolet or Halpha…
Irregular (Irr) galaxies are gas-rich objects with recent or ongoing star formation. In absence of spiral density waves, star formation occurs largely stochastically. The scattered star-forming regions tend to be long-lived and migrate…
We argue that, at least a fraction of the newly discovered population of ultra-faint dwarf spheroidal galaxies in the Local Group constitute the fossil relic of a once ubiquitous population of dwarf galaxies formed before reionization with…
Dwarf galaxies in the Local Group (LG) represent a distinct as well as diverse family of tracers of the earliest phases of galaxy assembly and the processing resulting from galactic harassment. Their stellar populations can be resolved and…
We revisit the scaling relations and star-forming histories of local elliptical galaxies using a novel selection method applied to the Sloan Digital Sky Survey DR7. We combine two probability-based automated spectroscopic and morphological…
We present Halpha narrow-band imaging of 17 dwarf irregular galaxies (dIs) in the nearby Centaurus A Group. Although all large galaxies of the group have a current or recent enhanced star formation episode, the dIs have normal star…
The formation of tidal dwarf galaxies (TDGs) is triggered by the encounters of already existing galaxies. Their existence is predicted from numerical calculations of encountering galaxies and is also well documented with observations. The…
We review basic properties of the population of dwarf galaxies in the Local Group focusing on dwarf spheroidal galaxies found in the immediate vicinity of the Milky Way. The evidence for dark matter in these objects is critically assessed.…
The star formation histories (SFHs) of galaxies provide valuable insights into galaxy evolution and stellar physics. Understanding the SFHs enables the study of chemical enrichment of galaxies, star formation triggered by interactions, and…
Dwarf spheroidal (dSph) galaxies present an evolutionary puzzle that we explore in 40 early- and late-type dwarfs in the Local Group and nearby field. Although dSphs formed stars over extended periods, today all but one are free of…
Galaxy morphologies in clusters have undergone a remarkable transition over the past several billion years. Distant clusters at $z \sim 0.4$ are filled with small spiral galaxies, many of which are disturbed and show evidence of multiple…
Prompted by a new catalogue of M31 globular clusters, we have collected together individual metallicity values for globular clusters in the Local Group. Although we briefly describe the globular cluster systems of the individual Local Group…
Deep surveys conducted during the past decades have shown that galaxies in the distant universe are generally of more irregular shapes, and are disky in appearance and in their star formation rate, compared to galaxies in similar…