Related papers: The hot interstellar medium towards 4U 1820-30: a …
Ionized carbon is the main gas-phase reservoir of carbon in the neutral diffuse interstellar medium and its 158 micron fine structure transition [CII] is the most important cooling line of the diffuse interstellar medium (ISM). We combine…
Diffuse ionized gas pervades the disk of the Milky Way. We detect extremely faint emission from this Galactic Warm Ionized Medium (WIM) using the Green Bank Telescope to make radio recombination line (RRL) observations toward two Milky Way…
The number of detected baryons in the Universe at z<0.5 is much smaller than predicted by standard big bang nucleosynthesis and by the detailed observation of the Lyman alpha forest at red-shift z=2. Hydrodynamical simulations indicate that…
We present the first X-ray detection of resonant absorption from warm/hot local gas either in our Galaxy, or in the Intergalactic space surrounding our Galaxy, along the line of sight toward the blazar PKS 2155-304. The Chandra HRCS-LETG…
The evolution of the temperature in the intergalactic medium is related to the reionization of hydrogen and helium, and has important consequences for our understanding of the Lya forest and of galaxy formation in gravitational models of…
We extend our time-dependent hydrogen ionization simulations of diffuse ionized gas to include metals important for collisional cooling and diagnostic emission lines. The combination of heating from supernovae and time-dependent collisional…
Recent theoretical and observational studies have shown that ashes from thermonuclear burning may be ejected during radius-expansion bursts, giving rise to photoionisation edges in the X-ray spectra. We report a search for such features in…
We present high-resolution UV spectra of absorption-line systems toward the low-z QSO HS0624+6907 (z=0.3700). Coupled with spectroscopic galaxy redshifts, we find that many of these absorbers are integalactic gas clouds distributed within…
We report on observations of several optical emission lines toward a variety of newly revealed faint, large-scale H-alpha-emitting structures in the warm ionized medium (WIM) of the Galaxy. The lines include [N II] 6583, [N II] 5755, [S II]…
We explore the multiphase structure of the circumgalactic medium (CGM) probed by synthetic spectra through a cosmological zoom-in galaxy formation simulation. We employ a Bayesian method for modelling a combination of absorption lines to…
We estimate the detectability of X-ray metal-line emission from the circumgalactic medium (CGM) of galaxies over a large halo mass range ($\mathrm{M}_{\mathrm{200c}} = 10^{11.5}$-$10^{14.5}\,\mathrm{M}_{\odot}$) using the EAGLE simulations.…
Hot ionized gas is observed in the local vicinity of our galaxy through spectral absorption features. The most common hypothesis is that this gas forms a halo surrounding our Milky-Way (MW), in collisional ionization equilibrium. In this…
Context. The high energies of protostellar jets, implied by recent observations of X-rays from such flows, came very much as a surprise. Inferred shock velocities are considerably higher than what was previously known, hence putting even…
We analyze interstellar absorption features in the full UV spectrum of the nearby (d = 24 pc) B8 IVn star alpha Leo (Regulus) obtained at high resolution and high S/N by the HST ASTRAL Treasury program. We derive column densities for many…
We have obtained new observations of the absorption system at $z_\mathrm{abs}=0.48$ toward QSO Q0454-220, which we use to constrain its chemical and physical conditions. The system features metal-enriched gas and previously unknown…
We selected 35 low-mass SFGs (7.9<log(M$_*$/M$_{\odot}$)<10.3) from deep spectroscopic surveys based on their CIII]1908 emission. We used follow-up NIR observations to examine their rest-optical emission lines and identify ionized outflow…
We study the composition of the Galactic interstellar medium (ISM) toward the Galactic center region (5 < |l| < 20 degree) by utilizing X-ray absorption features of three bright low-mass X-ray binaries (LMXBs), GX 13+1, GX 5-1, and GX…
We describe an extensive FUSE survey of highly ionized oxygen in the vicinity of the Milky Way that serves as an example of the type of study that would be desirable for other galactic systems. Understanding the origin of hot gas in the…
Low-ionization metal absorption lines provide a primary probe of cool gas in and around galaxies. We confront observations of metal-line absorption in quasar spectra with predictions from the IllustrisTNG cosmological simulation in order to…
We analyzed two XMM-Newton observations in the direction of the high density, high latitude, neutral hydrogen cloud MBM20 and of a nearby low density region that we called the Eridanus hole. The cloud MBM20 is at a distance evaluated…