Related papers: The evolution of dwarf galaxies in the Coma superc…
{abridged} We present imaging and spectroscopy of Abell 1689 (z=0.183) from GEMINI/GMOS-N and HST/ACS. We measure integrated photometry from the GMOS g' and r' images (for 531 galaxies) and surface photometry from the HST F625W image (for…
(Abridged) We analyze photometry and spectroscopy of a sample of 63 clusters at 0.3<z<0.9 drawn from the Las Campanas Distant Cluster Survey to empirically constrain models of cluster galaxy evolution. Specifically, by combining data on our…
We have selected a sample of local E+A galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 7 for follow up integral field spectroscopy with the Wide Field Spectrograph (WiFeS) on the ANU 2.3-m telescope. The sample was selected…
K band observations of the galaxy populations of three high redshift (z=0.8-1.0), X-ray selected, massive clusters are presented. The observations reach a depth of K = 21.5, corresponding to K*+3.5 mag. The evolution of the galaxy…
Using three newly identified galaxy clusters at z~1 (photometric redshift) we measure the evolution of the galaxies within clusters from high redshift to the present day by studying the growth of the red cluster sequence. The clusters are…
Gas-rich galaxies in dense environments such as galaxy clusters and massive groups are affected by a number of possible types of interactions with the cluster environment, which make their evolution radically different than that of field…
We use a complete, unbiased sample of 257 dwarf (10^8 MSun < Mstar < 10^9.5 MSun) galaxies at z < 0.08, in the COSMOS field, to study the morphological mix of the dwarf population in low-density environments. Visual inspection of extremely…
We carried out deep H$\alpha$ narrowband imaging with 10 hours net integrations towards the young protocluster, USS1558$-$003 at $z=2.53$ with the Subaru Telescope. This system is composed of four dense groups with massive local…
We recently identified a population of low surface brightness objects in the field of the z=0.023 Coma cluster, using the Dragonfly Telephoto Array. Here we present Keck spectroscopy of one of the largest of these "ultra-diffuse galaxies"…
We compare the star formation (SF) activity in cluster galaxies to the field from z=0.3-1.5 using $Herschel$ SPIRE 250$\mu$m imaging. We utilize 274 clusters from the IRAC Shallow Cluster Survey (ISCS) selected as rest-frame near-infrared…
Recent studies have shown that distant red galaxies (DRGs), which dominate the high-mass end of the galaxy population at z~2.5, are more strongly clustered than the population of blue star-forming galaxies at similar redshifts. However…
We have selected a sample of 88 nearby (z<0.1) galaxy clusters from the SDSS-DR4 with redshift information for the cluster members. We have derived global properties for each cluster, such as their mean recessional velocity, velocity…
We present HST/WFPC2 observations of the five bluest E+A galaxies (z~0.1) in the Zabludoff et al. sample to study whether their detailed morphologies are consistent with late-to-early type evolution and to determine what drives that…
With the help of a statistical parameter derived from optical spectra, we show that the current star formation rate of a galaxy, falling into a cluster along a supercluster filament, is likely to undergo a sudden enhancement before the…
We analyse a sample of twelve galaxy clusters, from the Kapteyn IAC WEAVE INT Cluster Survey (KIWICS) looking for dwarf galaxy candidates. By using photometric data in the $r$ and $g$ bands from the Wide Field Camera (WFC) at the 2.5-m…
We select E+A candidates from a spectroscopic dataset of ~800 field galaxies and measure the E+A fraction at 0.3<z<1 to be 2.7+/-1.1%, a value lower than that in galaxy clusters at comparable redshifts (11+/-3%). HST/WFPC2 imaging for five…
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…
Different compositions of galaxy types in the field in comparison to galaxy clusters as described by the morphology-density relation in the local universe is interpreted as a result of transformation processes from late- to early-type…
Postststarburst (K+A) galaxies are candidates for galaxies in transition from a star-forming phase to a passively-evolving phase. We have spectroscopically identified large samples of K+A galaxies both in the SDSS at z~0.1 and in the DEEP2…
We present long slit spectra and multi-color CCD images which demonstrate that the strong star formation episodes that occurred in the post-starburst galaxies in the Coma Cluster and two field galaxies were not restricted to the central…