Related papers: The Last Eight-Billion Years of Intergalactic SiIV…

Using the Cosmic Origins Spectrograph aboard the Hubble Space Telescope, we measured the abundances of six ions (C III, C IV, Si III, Si IV, N V, O VI) in the low-redshift (z < 0.4) intergalactic medium and explored C and Si ionization…

We present measurements of [SIII]$\lambda\lambda$9069,9531 for a sample of $z\sim1.5$ star-forming galaxies, the first sample with measurements of these lines at z>0.1. We employ the line ratio…

In this work, by using strong gravitational lensing (SGL) observations along with Type Ia Supernovae (Union2.1) and gamma ray burst data (GRBs), we propose a new method to study a possible redshift evolution of $\gamma(z)$, the mass density…

The goal of the Complete Optical and Radio Absorption Line System (CORALS) survey is to quantify the potential impact on QSO absorber statistics from dust in intervening galaxies. Dust may introduce a selection bias in surveys which are…

Moderate resolution spectra have been recorded for a sample of radio-selected QSOs (z=2.5) discovered in the ``Faint Images of the Radio Sky at Twenty centimeters'' (FIRST) VLA survey. This work is motivated by the study of a heterogeneous…

A small survey of the UV-absorbing gas in 12 low-$z$ galaxy groups has been conducted using the Cosmic Origins Spectrograph (COS) on-board the Hubble Space Telescope (HST). Targets were selected from a large, homogeneously-selected sample…

We have observed the much studied Seyfert 1 galaxy NGC5548 with the GHRS spectrometer on HST. Our 14ksec observation covers the CIV emission line at a resolution of >20,000. Our purpose was to study the absorption line found at lower…

We report new observations of the cool diffuse gas around 29, $2.3<z<6.3$ galaxies, using deep JWST/NIRCam slitless grism spectroscopy around the sightline to the quasar J0100+2802. The galaxies span a stellar mass range of $7.1 \leq \log…

We performed spectroscopic analyses of five local compact star-forming galaxies (CSFGs) with extremely high [OIII]/[OII] (O$_{32}$) ratios ($>20$). These targets remarkably share similar properties with high-redshift CIV emitters at $z>6$:…

We present an analysis of interstellar absorption lines in high-resolution optical echelle spectra of SS Cyg obtained during an outburst in 2013 June and in archival Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer data.…

We study the $z\approx3.5$ intergalactic medium (IGM) by comparing new, high-quality absorption spectra of eight QSOs with $\langle z_{\rm QSO} \rangle=3.75$, to virtual observations of the EAGLE cosmological hydrodynamical simulations. We…

We present a sample of 88 candidate z~8.5-14.5 galaxies selected from the completed NIRCam imaging from the Cosmic Evolution Early Release Science (CEERS) survey. These data cover ~90 arcmin^2 (10 NIRCam pointings) in six broad-band and one…

(Abbreviated) From six spectra of high-z QSOs, we select eleven metal-rich, Z>=Z_solar, and optically-thin to the ionizing radiation, N(HI)<10^17 cm^-2, absorption systems ranging between z=1.5 and z=2.9 and revealing lines of different…

We present results from a survey of weak MgII absorbers in the VLT/UVES spectra of 81 QSOs obtained from the ESO archive. In this survey, we identified 112 weak MgII systems within the redshift interval 0.4 < z < 2.4 with 86% completeness…

We present detailed photoionization models of well aligned optically thin C III absorption components at $2.1 < z < 3.4$. Using our models we estimate density ($n_{\rm \tiny H}$), metallicity ($[C/H]$), total hydrogen column density and…

(Modified) We measure the distribution of carbon in the intergalactic medium as a function of redshift z and overdensity delta. Using a hydrodynamical simulation to link the H I absorption to the density and temperature of the absorbing…

Results of a careful analysis of the highly ionized absorption systems, observed over the redshift range 2.198--2.2215 in the zem=2.24 HDFS-QSO J2233-606, are presented. Strong OVI and NeVIII absorptions are detected. Most of the lines show…

We report on the detection of a z_gal=0.101 galaxy projected on the sky at 4.2 arcsec (or 5.2 h^{-1} kpc for q_o=0.5) from the quasar Q 0439-433 (z_em=0.594). The HST spectrum of the quasar shows strong MgII, FeII, SiII, AlII and CIV…

We present a study of extended galaxy halo gas through HI and OVI absorption over two decades in projected distance at $z\approx0.2$. The study is based on a sample of $95$ galaxies from a highly complete ($ > 80\%$) survey of faint…

We present the results of a survey for CaII 3934,3969 absorption-line systems culled from ~ 95,000 Sloan Digital Sky Survey (SDSS) Data Release 7 and Data Release 9 quasar spectra. With 435 doublets identified in the catalog, this list is…