Related papers: Characterizing Transition Temperature Gas in the G…
Using spatially resolved, deprojected ROSAT PSPC spectra of 10 of the brightest cooling flow galaxies and groups with low Galactic column densities we have detected intrinsic absorption over energies ~0.4-0.8 keV in half of the sample.…
We present the results of a long (~93 ksec) XMM-Newton observation of the bright BL-Lac object PKS 0548-322 (z=0.069). Our Reflection Grating Spectrometer (RGS) spectrum shows a single absorption feature at an observed wavelength…
We present Far Ultraviolet Spectroscopic Explorer and Hubble Space Telescope observations of high, intermediate, and low ion absorption in high-velocity cloud Complex C along the lines of sight toward five active galaxies. Our purpose is to…
Radiative turbulent mixing layers should be ubiquitous in multi-phase gas with shear flow. They are a potentially attractive explanation for the high ions such as OVI seen in high velocity clouds and the circumgalactic medium (CGM) of…
We present ISO observations of the S(0), S(1), S(2), and S(3) rotational lines of molecular hydrogen from two molecular clouds near the Galactic Center (GC). We have also measured continuum dust emission at infrared wavelengths with ISO and…
There is mounting evidence for an extra-planar gas layer around the Milky Way disk, similar to the anomalous HI gas detected in a few other galaxies. As much as 10% of the gas may be in this phase. We analyze HI clouds located in the…
We discuss physical conditions in Galactic neutral hydrogen based on deep, high velocity resolution interferometric HI 21 cm absorption spectroscopy towards 33 compact extra-galactic radio sources. The HI 21 cm optical depth spectra have…
O VI absorption is observed in a wide range of astrophysical environments, including the Local ISM, the disk and halo of the Milky Way, high-velocity clouds, the Magellanic clouds, starburst galaxies, the intergalactic medium, damped…
We present direct measures of the ionization fractions of several sulfur ions in the Galactic warm ionized medium (WIM). We obtained high resolution ultraviolet absorption line spectroscopy of post-asymptotic giant branch stars in the the…
Large OVI columns are observed around star-forming, low-redshift ~L* galaxies, with a dependence on impact parameter indicating that most O^5+ particles reside beyond half the halo virial radius (>~100 kpc). In order to constrain the nature…
We have obtained high resolution FUSE and HST/STIS echelle observations of the quasar PG 1116+215. The semi-continuous coverage of the ultraviolet spectrum over the wavelength range 916-2800 provides detections of Galactic and high velocity…
We analyze the absorption and emission-line profiles produced by a set of simple, cool gas wind models motivated by galactic-scale outflow observations. We implement monte carlo radiative transfer techniques that track the propagation of…
We use Keck HIRES spectra of three intermediate redshift QSOs to study the physical state and kinematics of the individual components of CIV selected heavy element absorption systems. Fewer than 8 % of all CIV lines with column densities…
We present the results of a new sensitive survey of neutral hydrogen above and below the Galactic Center with the Green Bank Telescope. The observations extend up to Galactic latitude | b | < 10 deg with an effective angular resolution of…
We present a detailed spectroscopic study of the hot gas in the Galactic halo toward the direction of a blazer PKS 2155-304 (z=0.117). The OVII and OVIII absorption lines are measured with the Low and High Energy Transmission Grating…
The circumgalactic medium (CGM) of nearby star-forming galaxies shows clear indications of OVI absorption accompanied by little to no detectable NV absorption. This unusual spectral signature, accompanied by highly non-uniform absorption…
Based on measurements with the Effelsberg 100-m telescope, a multi-line study of molecular species is presented toward the gravitational lens system PKS1830-211. Obtaining average radial velocities and performing Large Velocity Gradient…
We study the ionization structure of galactic outflows in 37 nearby, star forming galaxies with the Cosmic Origins Spectrograph on the Hubble Space Telescope. We use the O I, Si II, Si III, and Si IV ultraviolet absorption lines to…
We present fully-sampled maps of 461 GHz CO (4-3), 807 GHz CO (7-6), and 492 GHz [CI] (3P1-3P0) emission from the inner 3 degrees of the Galactic Center region taken with the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO)…
We have recently identified several high velocity (V < -100 km/s) clouds in the directions of Mrk 509 and PKS 2155-304 that have unusual ionization properties. The clouds exhibit strong C IV absorption with little or no detectable low ion…