Related papers: EUV Emission from Normal Galaxies
Flux estimates for ionizing radiation escaping from star-forming galaxies with characteristic UV luminosities ($L^{*}_{1500(1+z)}$) derived from GALEX and the VIMOS-VLT Deep Survey, are presented as a function of redshift and assumed escape…
Galaxy counts from bright ultraviolet (UV) and deep optical spectroscopic surveys have revealed an unexpectedly large number of very blue galaxies. The colors and luminosities of these objects indicate that they are dwarf galaxies…
We report, for the first time, the long-awaited detection of diffuse gamma rays with energies between 100 TeV and 1 PeV in the Galactic disk. Particularly, all gamma rays above 398 TeV are observed apart from known TeV gamma-ray sources and…
Absorption-line spectroscopy of 23 background QSOs and numerous background galaxies has let us measure the spatial distribution of metals and neutral hydrogen around 1044 UV-selected galaxies at redshifts 1.8<z<3.3. The typical galaxy is…
Different types of extragalactic objects are known to produce TeV gamma-rays. Some of these objects are the most probable candidates to accelerate cosmic rays up to 10^20 eV. It is very well known that gamma-rays can be produced as a result…
We discuss a concept of a point-like source of the extreme ultraviolet (EUV) light based on a non-equilibrium microwave discharge in expanding jet of dense xenon plasma with multiply charged ions. A conversion efficiency of microwave…
Observations with the Extreme UltraViolet Explorer (EUVE) satellite have shown that the inner region of the Virgo cluster (centered in M87 galaxy) has a strong Extreme UltraViolet (EUV) emission (up to $13^{\prime}$) in excess to the…
39 galaxies are now known, from follow-up of faint IRAS sources and from submm observations of high redshift AGN, with far infrared luminosities > 10^{13} Lo. 13 of these, which have been found in 60 or 850 mu surveys, form an important…
Simultaneous measurements of air showers with the fluorescence and surface detectors of the Pierre Auger Observatory allow a sensitive search for EeV photon point sources. Several Galactic and extragalactic candidate objects are grouped in…
Archival EAS-MSU data are searched for anomalous muonless events which may be caused by primary gamma rays with energies between 10^15 eV and 10^18 eV. We consider a refined sample of high-quality data and confirm the previously reported…
We present a rest-UV selected sample of 32 lensed galaxies at $z\sim 2$ observed with joint Keck/LRIS rest-UV and Keck/MOSFIRE rest-optical spectra behind the clusters Abell 1689, MACS J0717, and MACS J1149. The sample pushes towards the…
The origin of ultra-high-energy cosmic rays remains one of the central open questions in astroparticle physics. Recent measurements reveal anisotropies in arrival directions, a rigidity-dependent composition dominated by intermediate-mass…
We present results of a re-analysis of archival EUVE data of the central region of the Virgo cluster. We employ the new analysis method developed by Bowyer, Bergh\"ofer & Korpela (1999) and find diffuse emission reaching out to a distance…
We present the results of a photometric redshift analysis designed to identify z>6 galaxies from the near-IR HST imaging in three deep fields (HUDF, HUDF09-2 & ERS). By adopting a rigorous set of criteria for rejecting low-z interlopers,…
We investigate the intrinsic opacity of high-redshift galaxies to outgoing ionising photons using high-quality photometry of a sample of 27 spectroscopically-identified galaxies of redshift 1.9<z<3.5 in the Hubble Deep Field. Our…
From an analysis of almost 2000 GALEX images of galaxies with morphological types ranging from E to Sab, we have found a significant subset (28%) that show UV emission outside $R_{25}$. We have obtained H$\alpha$ imaging of ten such…
Despite much observational and theoretical effort little is presently known about the nature of the luminous non-nuclear X-ray sources which appear to largely surpass the Eddington limit of a few solar masses. Here we present first results…
Clustering of cosmic-ray sources affects the flux observed beyond the cutoff imposed by the cosmic microwave background and may be important in interpreting the AGASA, Fly's Eye, and HiRes data. The standard deviation, sigma, in the…
Various independent ways of constraining the Hubble constant and the baryonic content of the universe finally converged at a consensus range of values which indicates that at the present epoch the bulk of the universe's baryons is in the…
The bright gamma-ray quasar 4C +55.17 is a distant source ($z = 0.896$) with a hard spectrum at GeV energies as observed by the Large Area Telescope (LAT) on board the {{\it Fermi}} satellite. This source is identified as a good source…