Related papers: A study of the merging dwarf galaxy VCC322
Data products from the Advanced Camera for Surveys Virgo Cluster Survey are used to understand the bulge star formation history in early-type galaxies at redshifts z > 2. A new technique is developed whereby observed high-redshift…
We present new Gemini spectra of 14 new objects found within the HI tails of Hickson Compact Groups 92 and 100. Nine of them are GALEX Far-UV (FUV) and Near-UV (NUV) sources. The spectra confirm that these objects are members of the compact…
Galaxy interaction and merging have clear effects on the systems involved. We find an increase in the star formation rate (SFR), potential ignition of active galactic nuclei (AGN) and significant morphology changes. However, at what stage…
For a rotating galaxy, the inner circular-velocity gradient d_{R}V(0) provides a direct estimate of the central dynamical mass density, including gas, stars, and dark matter. We consider 60 low-mass galaxies with high-quality HI and/or…
We present a population synthesis study of NGC4435, an early-type Virgo galaxy interacting with NGC4438. We combine new spectroscopic observations obtained with the Spitzer Space Telescope IRS instrument with IRAC archival data and broad…
Recent observations of ram pressure stripped spiral galaxies in clusters revealed details of the stripping process, i.e., the truncation of all interstellar medium (ISM) phases and of star formation (SF) in the disk, and multiphase…
We use a sample of close galaxy pairs selected from the Sloan Digital Sky Survey Data Release 4 (SDSS DR4) to investigate in what environments galaxy mergers occur and how the results of these mergers depend on differences in local galaxy…
We present deep HST/ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical. Our new images reveal dramatic shell structure indicative of a merger event in the relatively…
The observational consequences of the merger scenario for massive star formation are explored and contrasted with the gradual accumulation of mass by accretion. Protostellar mergers may produce high luminosity infrared flares lasting years…
We present stellar age profiles for 64 Virgo cluster disk galaxies whose analysis poses a challenge for current galaxy formation models. Our results can be summarized as follows: first, and contrary to observations of field galaxies, these…
Compact group galaxies often appear unaffected by their unusually dense environment. Closer examination can, however, reveal the subtle, cumulative effects of multiple galaxy interactions. Hickson Compact Group (HCG) 59 is an excellent…
We present a new model for the formation of stellar halos in dwarf galaxies. We demonstrate that the stars and star clusters that form naturally in the inner regions of dwarfs are expected to migrate from the gas rich, star forming centre…
We report our study of features at the observed red end of the white dwarf cooling sequences for three Galactic globular clusters: NGC\,6397, 47\,Tucanae and M\,4. We use deep colour-magnitude diagrams constructed from archival Hubble Space…
We have employed FORS1/2+VLT to acquire deep B and R CCD images of 16 dwarf elliptical galaxies in the direction of the Virgo cluster. For each dwarf we measure the R-band surface brightness fluctuation (SBF) magnitude \bar{m}_R and the…
We study star formation in a sample of 1204 galaxies in minor (| \Delta m_z | \geq 2) pairs and compact groups, drawn from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5). We analyze an analogous sample of 2409 galaxies in major (|…
In the local Universe, the existence of very young galaxies (VYGs), having formed at least half their stellar mass in the last 1 Gyr, is debated. We predict the present-day fraction of VYGs among central galaxies as a function of galaxy…
We present the results of a Keck spectroscopic study of globular clusters associated with the Virgo Cluster dwarf elliptical VCC 1386. We analyze blue spectroscopic absorption lines from 3500-5500 A for 13 globular cluster candidates and…
The galaxy correlation function serves as a fundamental tool for studying cosmology, galaxy formation, and the nature of dark matter. It is well established that more massive, redder and more compact galaxies tend to have stronger…
We report the measured H$\alpha$ fluxes and images of 66 nearby objects observed with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. Three of these objects: IC2233, UGC4704, and NGC3432 are…
Using V and I images obtained with WFPC2/HST, we investigate compact stellar structures within tidal tails. Six regions of tidal debris in the four classic ``Toomre Sequence'' mergers: NGC 4038/39 (``Antennae''), NGC 3256, NGC 3921, and NGC…