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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 at z < 0.2 with the Space Telescope Imaging Spectrograph. CGM warm cloud properties are derived, including volume filling factors of 3-5%, cloud sizes of 0.1-30 kpc, masses of 10-1e8 solar masses and metallicities of 0.1-1 times solar. Almost all warm CGM clouds within 0.5 virial radii are metal-bearing and many have velocities consistent with being bound, galactic fountain clouds. For galaxies with L > 0.1 L*, the total mass in these warm CGM clouds approaches 1e10 solar masses, ~10-15% of the total baryons in massive spirals and comparable to the baryons in their parent galaxy disks. This leaves >50% of massive spiral-galaxy baryons missing. Dwarfs (<0.1 L*) have smaller area covering factors and warm CGM masses (<5% baryon fraction), suggesting that many of their warm clouds escape. Constant warm cloud internal pressures as a function of impact parameter ($P/k ~ 10 cm^{-3} K) support the inference that previous COS detections of broad, shallow O VI and Ly-alpha absorptions are of an extensive (~400-600 kpc), hot (T ~ 1e6 K) intra-cloud gas which is very massive (>1e11 solar masses). While the warm CGM clouds cannot account for all the missing baryons in spirals, the hot intra-group gas can, and could account for ~20% of the cosmic baryon census at z ~ 0 if this hot gas is ubiquitous among spiral groups.
We present basic data and modeling for a survey of the cool, photo-ionized Circum-Galactic Medium (CGM) of low-redshift galaxies using far-UV QSO absorption line probes. This survey consists of targeted and serendipitous CGM subsamples, originally de
To characterize the absorption properties of this circumgalactic medium (CGM) and its relation to the LG we present the so-far largest survey of metal absorption in Galactic high-velocity clouds (HVCs) using archival ultraviolet (UV) spectra of extra
Active Galactic Nuclei often show evidence of photoionized outflows. A major uncertainty in models for these outflows is the distance ($R$) to the gas from the central black hole. In this paper we use the HST/COS data from a massive multi-wavelength
The circumgalactic medium (CGM), which harbors > 50% of all the baryons in a galaxy, is both the reservoir of gas for subsequent star formation and the depository of chemically processed gas, energy, and angular momentum from feedback. As such, the C
We present preliminary results on the low-redshift Lyman alpha forest as based on STIS spectra of 3C 273. A total of 121 intergalactic Lyman alpha-absorbing systems were detected, of which 60 are above the 3.5 sigma completness limit, log N(HI)~12.3.