Related papers: A Detailed Analysis of a Cygnus Loop Shock-Cloud I…
The Cygnus Superbubble (CSB) is a region of soft X-ray emission approximately 13 degrees wide in the direction of the local spiral arm. Such a large region might be the result of strong stellar winds and supernovae from nearby stellar…
The Far Ultraviolet Spectroscopic Explorer (FUSE) has observed over three hundred fifty sightlines to extragalactic targets. About one hundred fifty of these are of sufficient quality to measure OVI absorption in and near the Milky Way.…
We present results from an analysis of FUSE and HST/STIS spectroscopy of the z_em=0.57 quasar PKS0405-123. We focus on the intervening metal-line systems identified along the sightline and investigate their ionization mechanism, ionization…
Using EUV photometry obtained with the Extreme Ultraviolet Explorer (EUVE) satellite and UBVR optical photometry obtained with the 2.7-m telescope at McDonald Observatory, we have detected quasi-coherent oscillations (so-called ``dwarf nova…
Strong intergalactic shocks are a natural consequence of structure formation in the universe. These shocks are expected to deposit large fractions of their energy in relativistic electrons (xi_e~0.05 of the thermal energy according to…
Cygnus X is one of the most complex areas in the sky. This complicates interpretation, but also creates the opportunity to investigate accretion into molecular clouds and many subsequent stages of star formation, all within one small field…
We analyze a pair of Suzaku shadowing observations in order to determine the X-ray spectrum of the Galaxy's gaseous halo. We simultaneously fit the spectra with models having halo, local, and extragalactic components. The intrinsic…
We report Chandra ACIS and quasi-simultaneous RXTE observations of the nearby, powerful radio galaxy Cygnus A, with the present paper focusing on the properties of the active nucleus. In the Chandra observation, the hard (> a few keV) X-ray…
N66/NGC346 is the largest and brightest HII region in the Small Magellanic Cloud and contains at least one known supernova remnant SNR0057-7226. Optical emission from the remnant is overwhelmed by the bright photoionized emission from the…
Using three-dimensional magnetohydrodynamics simulations, we investigate general properties of a blast wave shock interacting with interstellar clouds. The shock-cloud interaction generates a turbulent shell through the vorticity…
The observational constraints on the baryon content of the WHIM rely almost entirely on FUV measurements. However, cosmological, hydrodynamical simulations predict strong correlations between the spatial distributions of FUV and X-ray…
We report the discovery of large ionized, [O II] emitting circumgalactic nebulae around the majority of thirty UV luminous quasars at $z=0.4-1.4$ observed with deep, wide-field integral field spectroscopy (IFS) with the Multi-Unit…
We have analyzed the deep Chandra observation (~155 ks) of the Compton Thick Active Galactic Nucleus (CT AGN) ESO 428-G014, to study in detail the morphology of the diffuse X-ray emission in the inner ~500 pc radius region. Comparing…
Context: While star formation on large molecular cloud scales and on small core and disk scales has been investigated intensely over the past decades, the connection of the large-scale interstellar material with the densest small-scale…
The Galactic supernova remnant (SNR) Cygnus Loop emerges as an ideal laboratory for analyzing the different radiation mechanisms, as well as the particle acceleration mechanisms at different types of shocks. In order to determine radio…
Optical diagnostic diagrams are frequently ambiguous as a test of the photoionization or fast shock models of the narrow line regions of active galaxies. Here, we present a set of UV line ratio diagrams which can discriminate between pure…
We performed spectroscopic analyses of five local compact star-forming galaxies (CSFGs) with extremely high [OIII]/[OII] (O$_{32}$) ratios ($>20$). These targets remarkably share similar properties with high-redshift CIV emitters at $z>6$:…
We study the ovi distribution in space and time in a representative section of the Galactic disk by 3D adaptive mesh refinement HD and MHD simulations of the ISM, including the disk-halo-disk circulation. The simulations describe a…
We analyze the high-resolution X-ray spectrum of the supergiant O-star delta Orionis (O9.5II) with line ratios of He-like ions and a thermal plasma model, and we examine its variability. The O-supergiant delta Ori was observed in the…
We report on Cyg X-1 observations performed by the SPI telescope onboard the INTEGRAL mission and distributed over more than 6 years. We investigate the variability of the intensity and spectral shape of this peculiar source in the hard…