Related papers: Tracing baryons in the warm-hot intergalactic medi…

Recent far-ultraviolet (FUV) absorption line measurements of low-redshift quasars have unveiled a population of intervening broad HI Lya absorbers (BLAs) with large Doppler parameters (b> 40 km/s). If the large width of these lines is…

We investigate the physical state of HI absorbing gas at low redshift (z = 0.25) using a subset of cosmological, hydrodynamic simulations from the OWLS project, focusing in particular on broad (b_HI > 40 km/s) HI Lyman-Alpha absorbers…

Thermally broadened Ly alpha absorbers (BLAs) offer an alternative method to highly-ionized metal lines for tracing the WHIM. We compile a catalog of reliable BLA candidates along seven AGN sight lines from a larger set of Lya absorbers…

We present a study of the Ly\alpha forest at z<0.4 from which we conclude that at least 20% of the total baryons in the universe are located in the highly-ionized gas traced by broad Ly\alpha absorbers. The cool photoionized low-z…

A large fraction of the baryon budget at $z<1$ resides in large-scale filaments in the form of diffuse intergalactic gas, and numerous studies have reported a significant correlation between the strength of the absorptions produced by this…

Thermally-broadened Lya absorbers (BLAs) offer an alternate method to using highly-ionized metal absorbers (OVI, OVII, etc.) to probe the warm-hot intergalactic medium (WHIM, T=10^5-10^7 K). Until now, WHIM surveys via BLAs have been no…

We describe our surveys of low column density Lyman-alpha absorbers [N(HI) = 10^(12.5-16.0) cm^-2], which show that the warm photoionized IGM contains 30% of all baryons at z < 0.1. This fraction is consistent with cosmological simulations,…

We present an analysis of the Lyman alpha forests of five quasar spectra in the near UV. Properties of the intergalactic medium (IGM) at an intermediate redshift interval (0.9 < z < 1.9) are studied. The amount of baryons in the diffuse…

We present a detection of a broad Ly-alpha absorber (BLA) with a matching O VI line in the nearby universe. The BLA is detected at z = 0.01028 in the high S/N spectrum of Mrk 290 obtained using the Cosmic Origins Spectrograph. The Ly-alpha…

Observations of the QSO HE 0226-4110 (zem = 0.495) with the Cosmic Origins Spectrograph (COS) from 1134 to 1796 {\AA} with a resolution of ~17 km s-1 and signal-to- noise (S/N) per resolution element of 20 to 40 are used to study the…

Cosmological simulations predict that a significant fraction of the low-$z$ baryon budget resides in large-scale filaments in the form of a diffuse plasma at temperatures $T \sim 10^{5} - 10^{7}$ K. However, direct observation of this…

We use FUSE and STIS spectra to study intergalactic absorption towards the quasar PG1259+593 (z=0.478). We identify 135 intergalactic absorption lines with equivalent widths >10mA, tracing 78 absorption components in 72 Ly alpha/beta…

The low-redshift Ly-alpha forest of absorption lines provides a probe of large-scale baryonic structures in the intergalactic medium, some of which may be remnants of physical conditions set up during the epoch of galaxy formation. We…

We discuss physical properties and the baryonic content of the Warm-hot Intergalactic Medium (WHIM) at low redshifts. Cosmological simulations predict that the WHIM contains a large fraction of the baryons at z=0 in the form of…

We present HST and FUSE observations of the intergalactic absorption toward PG1116+215 in the 900-3000 A spectral region. We detect 25 Ly-alpha absorbers at rest-frame equivalent widths W_r > 30 mA, yielding (dN/dz)_Ly-alpha = 154+/-18 over…

The intergalactic medium (IGM) is the dominant reservoir of baryons at all cosmic epochs. We investigate the evolution of the IGM from z=2-0 in 48 Mpc/h, 110-million particle cosmological hydrodynamic simulations using three prescriptions…

The relationship between galaxies and the state/chemical enrichment of the warm-hot intergalactic medium (WHIM) expected to dominate the baryon budget at low-z provides sensitive constraints on structure formation and galaxy evolution…

We explore the possibility to systematically study the extended, hot gaseous halos of low-redshift galaxies with Coronal Broad Ly alpha Absorbers (CBLAs). These are weak, thermally broadenend HI absorption lines arising from the tiny…

We report the discovery of two low redshift HI 21cm absorbers, one at z = 0.2212 towards the z_{em} = 0.630 quasar OI 363 (B0738+313), and the other at z = 0.3127 towards PKS B1127-145 (z_{em} = 1.187). Both were found during a survey of…

We report on the observed properties of the plasma revealed through high signal-to-noise (S/N) observations of 54 intervening O VI absorption systems containing 85 O VI and 133 H I components in a blind survey of 14 QSOs observed at ~18 km…