Related papers: Background X-ray Radiation Fields Produced by Youn…
The young star clusters we observe today are the building blocks of a new generation of stars and planets in our Galaxy and beyond. Despite their fundamental role we still lack knowledge about the conditions under which star clusters form…
Recent observations have suggested that circumstellar disks may commonly form around young stellar objects. Although the formation of circumstellar disks can be a natural result of the conservation of angular momentum in the parent cloud,…
Massive young star clusters contain dozens or hundreds of massive stars that inject mechanical energy in the form of winds and supernova explosions, producing an outflow which expands into their surrounding medium, shocking it and forming…
We have examined the spatial distribution of substructure in clusters of galaxies using Einstein X-ray observations. Subclusters are found to have a markedly anisotropic distribution that reflects the surrounding matter distribution on…
Their ubiquity and extreme densities make star clusters probes of prime importance of galaxy evolution. Old globular clusters keep imprints of the physical conditions of their assembly in the early Universe, and younger stellar objects,…
Recent observations with the Extreme Ultraviolet Explorer (EUVE) suggest that at least some clusters of galaxies are luminous sources of extreme ultraviolet (EUV) radiation. It is not clear yet whether EUV emission is a general feature of…
Hot intergalactic gas in clusters, groups, and filaments emanates a continuous background of 0.5-2.0 keV X-rays that ought to be detectable with the new generation of X-ray observatories. Here we present selected results from a program to…
We investigate the environmental dependence of star formation in cluster virial regions and infall regions as part of CAIRNS (Cluster And Infall Region Nearby Survey), a large spectroscopic survey of the infall regions surrounding nine…
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…
Young stars are surrounded by copious amounts of circumstellar material. Its composition, in particular its gas-to-dust ratio, is an important parameter. However, measuring this ratio is challenging, because gas mass estimates are often…
We examine the origin of clustercentric gradients in the star formation rates and colors of rich cluster galaxies within the context of a simple model where clusters are built through the ongoing accretion of field galaxies. The model…
We present Hubble Space Telescope near-IR spectroscopy for 18 galaxy clusters at 1.0 < $z$ < 1.5 in the IRAC Shallow Cluster Survey. We use Wide Field Camera 3 grism data to spectroscopically identify H$\alpha$ emitters in both the cores of…
Observations of the spatial distributions of young stars in star-forming regions can be linked to the theory of clustered star formation using spatial statistical methods. The MYStIX project provides rich samples of young stars from the…
We argue that the observed correlation between the radio luminosity and the X-ray luminosity in radio emitting galaxy clusters implies that the radio emission is due to secondary electrons that are produced by p-p interactions and lose…
The X-ray background (XRB) is produced by a large number of faint sources distributed over a wide range of redshifts. The XRB carries information on the spatial distribution and evolution of these sources. The goals of the paper are: 1. to…
Cosmic-ray scatterings on the cosmic neutrino background induce a flux of gamma-rays and X-rays from boosted meson decays and charged lepton processes. Here we present the first estimate of this flux and its cumulative cosmological…
Stellar feedback in the form of radiation pressure and magnetically-driven collimated outflows may limit the maximum mass that a star can achieve and affect the star-formation efficiency of massive pre-stellar cores. Here we present a…
The current models of early star and galaxy formation are based upon the hierarchical growth of dark matter halos, within which the baryons condense into stars after cooling down from a hot diffuse phase. The latter is replenished by infall…
Many disc galaxies in clusters have been found with bulges of similar age or younger than their surrounding discs, at odds with field galaxies of similar morphology and their expected inside-out formation. We use the EAGLE simulations to…
Stars form when filaments and dense cores in molecular clouds fragment and collapse due to self-gravity. In the most basic analyses of gravitational stability, the competition between self-gravity and thermal pressure sets the critical…