相关论文: Spatial Distribution of the Starbursts in Post-Sta…
The fraction of star-forming galaxies in rich clusters of galaxies increases rapidly with the redshift. This is interpreted as the result of a rapid evolution of cluster galaxies, though its mechanism is not yet clear. One hypothesis is…
A significant fraction of clusters of galaxies are observed to have substructure, which implies that merging between clusters and subclusters is a rather common physical process of cluster formation. It still remains unclear how cluster…
In this paper I present some recent and new results regarding the effects of the cluster environment on the star formation history of galaxies. Three main aspects are discussed: the differences in the stellar population ages of cluster…
HST WFPC2 images in B (F450W) and I (F814W) have been obtained for three starburst (SB) and two post-starburst (PSB) galaxies in the Coma cluster, and for three such galaxies in the cluster DC2048-52. V (F555W) and I images for an…
We map the spatial distribution of recent star formation over a few x 100 Myr timescales in fifteen starburst dwarf galaxies using the location of young blue helium burning stars identified from optically resolved stellar populations in…
The quenching mechanisms of galaxies are not yet fully understood, but post-starburst galaxies provide one explanation for the rapid transition between star-forming and quiescent galaxies. At low redshift, it is generally thought that the…
Optical and X-ray studies have established the prevalence of significant substructure in clusters of galaxies, indicating that clusters are young systems, and that recent major mergers have occurred in many clusters. Numerical simulations…
One of the most prominent features of galaxy clusters is the presence of a dominant population of massive ellipticals in their cores. Stellar archaeology suggests that these gigantic beasts assembled most of their stars in the early…
(Abridged) The building blocks of galaxies are star clusters. These form with low-star formation efficiencies and, consequently, loose a large part of their stars that expand outwards once the residual gas is expelled by the action of the…
The spectroscopic properties of galaxies in the Coma cluster are compared with those of galaxies in rich clusters at $z \sim 0.5$, to investigate the evolution of the star formation history in clusters. Luminous galaxies with $M_V \leq -20$…
At high redshift, starburst galaxies present irregular morphologies, with 10-20\%\ of their star formation occurring in giant clumps. These clumpy galaxies are considered to be the progenitors of local disk galaxies. To understand the…
Recent high-resolution observations with the Hubble Space Telescope (HST) reveal that young star clusters of extraordinary luminosity and compactness ("super star clusters") are commonly found in starburst systems. Cluster formation appears…
We present multi-fiber spectroscopy and broadband imaging of early-type galaxies in five nearby rich clusters of galaxies. The main purpose was to look for ``abnormal'' spectrum galaxies (i.e., post-starburst galaxies which have strong…
Although the existence of a faint background of starlight in the core of the Coma cluster has been well established (1,2), its origin is uncertain. This vast sea of stars could have formed outside the galaxies, using gas left over from the…
We have studied 116 bright galaxies from the Coma cluster brighter than $m_{r}=17$ mag. From a quantitative morphological analysis we find that the scales of the disks are smaller than those of field spiral galaxies. There is a correlation…
I will discuss the presence of massive star clusters in starburst galaxies with an emphasis on low mass galaxies outside the local group. I will show that such galaxies, with respect to their mass and luminosity, may be very rich in young…
Galactic nuclei often harbor a disproportionately large amount of star formation activity with respect to their surrounding disks. Not coincidentally, the density of molecular material in galactic nuclei is often also much greater than that…
Recently, very massive compact stellar systems have been discovered in the intracluster regions of galaxy clusters and in the nuclear regions of late-type disk galaxies. It is unclear how these compact stellar systems -- known as…
We study the shape and evolution of the star formation main sequence in three independently developed semi-analytic models of galaxy formation. We focus, in particular, on the characterization of the model galaxies that are significantly…
Star clusters stand at the intersection of much of modern astrophysics: the interstellar medium, gravitational dynamics, stellar evolution, and cosmology. Here we review observations and theoretical models for the formation, evolution, and…