Related papers: Star-Formation Knots in IRAS Galaxies
Star formation occurs on physical scales corresponding to individual star forming regions, typically of order ~100 parsecs in size, but current observational facilities cannot resolve these scales within field galaxies beyond the local…
We present a comprehensive study of ISO cluster galaxies in connection with other wavelengths. First results show that infrared galaxies detected by ISOCAM concentrate on the edge of clusters. Surprisingly, they are not emission lines…
We present some highlights from the mid-infrared (5-16 micron) images of mergers of massive galaxies obtained with the Infrared Space Observatory (ISO). We have observed: 1) ultraluminous infrared nuclei, 2) luminous dust-enshrouded…
From observations of edge-on, late-type galaxies, we present morphological evidence that some nuclear star clusters have experienced in situ star formation. We find three nuclear clusters that, viewed from the edge-on perspective, have both…
We compare mid-infrared images of the Antennae galaxies (NGC 4038/39) from the Infrared Space Observatory, with optical images from the Hubble Space Telescope. The mid-infrared observations show that the most intense starburst in this…
Galaxy-galaxy interactions rearrange the baryons in galaxies and trigger substantial star formation; the aggregate effects of these interactions on the evolutionary histories of galaxies in the Universe are poorly understood. We combine B…
A large body of evidence has demonstrated that the global rest-frame optical and IR colours of galaxies correlate well with each other, as well as with other galactic properties such as surface brightness and morphology. However the…
ISOCAM extragalactic mid-infrared deep surveys have detected a population of strong IR emitters ten times more numerous than expected if there were no evolution from z<0.2 (IRAS) up to the maximum redshift of these galaxies (z=1.5). The…
Star formation is triggered in essentially three ways: (1) the pressures from existing stars collect and squeeze nearby dense gas into gravitationally unstable configurations, (2) random compression from supersonic turbulence makes new…
Polar-ring galaxies are systems with two nearly orthogonal rotational axes, and are therefore clearly the result of galaxy-galaxy interactions. The host galaxies of polar rings are typically gas-poor early-type systems. The rings…
We present infrared luminosities, star formation rates, colors, morphologies, locations, and AGN properties of 24 micron-detected sources in photometrically detected high-redshift clusters in order to understand the impact of environment on…
We investigate the evolutionary connection between local IR-bright galaxies ($\log L_{\rm IR}\ge 11.4\,L_\odot$) and quasars. We use high angular resolution ($\sim$ 0.3-0.4 arcsec $\sim$ few hundred parsecs) $8-13\,\mu$m ground-based…
Most star complexes are in fact complexes of stars, clusters and gas clouds; term "star complexes" was introduced as general one disregarding the preferential content of a complex. Generally the high rate of star formation in a complex is…
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 present images of the peculiar galaxy Arp~10 which reveal two rings of concurrent star formation. Apart from a bright ring visible on early photographs of the system, an even brighter inner ring of \ion{H}{2} regions is found within the…
Several models have predicted that stars could form inside galactic outflows and that this would be a new major mode of galaxy evolution. Observations of galactic outflows have revealed that they host large amounts of dense and clumpy…
Massive stars form deeply embedded in their parental clouds, making it challenging to directly observe these stars and their immediate environments. It is known that accretion and ejection processes are intrinsically related, thus observing…
Aims. Filamentary structures of early type stars are found to be a common feature of the Magellanic Clouds formed at an age of about 0.9-2*10^8 yr. As we go to younger ages these large structures appear fragmented and sooner or later form…
The properties and star formation processes in the far-outer disks of nearby spiral and dwarf irregular galaxies are reviewed. The origin and structure of the generally exponential profiles in stellar disks is considered to result from…
The discovery of a large population of intra-cluster star clusters in the central region of the Hydra I and Centaurus galaxy clusters is presented. Based on deep VLT photometry (V,I), many star clusters have been identified not only around…