Related papers: Massive Warm/Hot Galaxy Coronae: II. Isentropic Mo…
Disc galaxies like the Milky Way are expected to be surrounded by massive coronae of hot plasma that may contain a significant fraction of the so-called missing baryons. We investigate whether the local (|vLSR|<400 km/s) warm-hot absorption…
We present a study comparing OVI $\lambda\lambda$1031, 1037 doublet absorption found towards group galaxy environments with that of isolated galaxies. The OVI absorption in the circumgalactic medium (CGM) of isolated galaxies has been…
Models of galaxy formation in a CDM universe predict that massive galaxies are surrounded by a hot, quasi-hydrostatic circumgalactic corona of slowly cooling gas, predominantly accreted from the IGM. This prediction is borne out by the…
We study the hot and cold circum-galactic medium (CGM) of 86 galaxies of the cosmological, hydrodynamical simulation suite NIHAO. NIHAO allows a study of how the $z=0$ CGM varies across 5 orders of magnitude of stellar mass using OVI and HI…
We present a study of the properties of the transition temperature (T~10^5 K) gas in the Milky Way corona, based on measurements of OVI, NV, CIV, SiIV and FeIII absorption lines seen in the far ultraviolet spectra of 58 sightlines to…
Observational evidence shows that low-redshift galaxies are surrounded by extended haloes of multiphase gas, the so-called 'circumgalactic medium' (CGM). To study the survival of relatively cool gas (T < 10^5 K) in the CGM, we performed a…
Results are presented for our search for warm-hot gas towards the quasar Q 0329-385. We identify ten OVI systems of which two are within 5000 km/s of z_em and a third one should be of intrinsic origin. The seven remaining systems have HI…
With high resolution (0.46kpc/h), adaptive mesh-refinement Eulerian cosmological hydrodynamic simulations we compute properties of O VI and O VII absorbers from the warm-hot intergalactic medium (WHIM). Our new simulations are in broad…
The Circumgalactic Medium (CGM) of late-type galaxies is characterized using UV spectroscopy of 11 targeted QSO/galaxy pairs at z < 0.02 with the Hubble Space Telescope Cosmic Origins Spectrograph and ~60 serendipitous absorber/galaxy pairs…
We present a simple model that explains the origin of warm diffuse gas seen primarily as highly ionized absorption line systems in the spectra of background sources. We predict the observed column densities of several highly ionized…
Diffuse hot gas can be traced effectively by its X-ray absorption and emission. We present a joint-analysis of these tracers to characterize the spatial and temperature distributions of the Galactic hot gas along the sight-line toward the…
The circumgalactic medium (CGM) remains one of the least constrained components of galaxies and as such has significant potential for advancing galaxy formation theories. In this work, we vary the extragalactic ultraviolet background for a…
The galactic gaseous halo is a gas reservoir for the interstellar medium in the galaxy disk, supplying materials for star formation. We developed a gaseous halo model connecting the galaxy disk and the gaseous halo by assuming the star…
The pervasive presence of warm gas in galaxy halos suggests that the circumgalactic medium (CGM) is multiphase in its ionization structure and complex in its kinematics. Some recent state-of-the-art cosmological galaxy simulations predict…
X-ray absorption lines of highly-ionized species such as OVII at about zero redshift have been firmly detected in the spectra of several active galactic nuclei. However, the location of the absorbing gas remains a subject of debate. To…
The circumgalactic medium (CGM) around galaxies is believed to record various forms of galaxy feedback and contain a significant portion of the "missing baryons" of individual dark matter halos. However, clear observational evidence for the…
The origin of warm ions in the circum-galactic medium (CGM) surrounding massive galaxies remains a mystery. In this paper, we argue that a significant fraction of the observed warm-ion columns may arise in the intergalactic medium (IGM)…
In preparation for a Hubble Space Telescope (HST) observing project using the Cosmic Origins Spectrograph (COS), the positions of all AGN targets having high-S/N far-UV G130M spectra were cross-correlated with a large catalog of…
We present basic data and modeling for a survey of the cool, photo-ionized Circum-Galactic Medium (CGM) of low-redshift galaxies using far-UV QSO absorption line probes. This survey consists of "targeted" and "serendipitous" CGM subsamples,…
We use adaptive mesh refinement cosmological simulations to study the spatial distribution and covering fraction of OVI absorption in the circumgalactic medium (CGM) as a function of projected virial radius and azimuthal angle. We compare…