Related papers: Quasars probing intermediate redshift star-forming…

We present JWST/NIRSpec R~2700 spectra of four high-redshift quasars: VDES J0020-3653 (z = 6.860), DELS J0411-0907 (z = 6.825), UHS J0439+1634 (z = 6.519) and ULAS J1342+0928 (z = 7.535). The exquisite data quality, signal-to-noise ratio of…

Gas surrounding high redshift galaxies has been studied through observations of absorption line systems toward background quasars for decades. However, it has proven difficult to identify and characterize the galaxies associated with these…

We present a catalogue of MgII absorption systems obtained from high resolution UVES/VLT data of 77 QSOs in the redshift range 0.6 < z < 2.0, and down to an equivalent width W_0 > 0.1 \AA. The statistical properties of our sample are found…

We use optical and near-IR imaging to examine the properties of the significant excess population of K>=19 galaxies found in the fields of 31 z=1-2 radio-loud quasars by Hall, Green & Cohen (1998). The excess occurs on two spatial scales: a…

We investigate the extent and the properties of the MgII cool, low-density absorbing gas located in the halo and in the circum-galactic environment of quasars, using a sample of 31 projected quasar pairs with impact parameter pd<200kpc in…

We have searched for redshifted absorption in the 21 cm line of neutral hydrogen toward `red quasars', which are extragalactic radio sources with a steep spectral drop between optical and infrared wavelengths. The success rate for detecting…

We searched for 21-cm absorption associated with the z_abs = 1.3647 absorption system toward PKS 0237-233 using the GMRT. A high quality UVES spectrum shows that C I and C I* are detected at this redshift together with C II*, Mg I, Mg II,…

Extreme emission-line galaxies (EELGs) at redshift z=1-2 provide a unique view of metal-poor, starburst sources that are the likely drivers of the cosmic reionization at z$\geq6$. However, the molecular gas reservoirs of EELGs - the fuel…

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…

Using high resolution, high signal-to-noise ultraviolet spectra of the z = 0.9754 quasar PG1148+549 obtained with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope, we study the physical conditions and abundances of…

The Complete Optical and Radio Absorption Line System (CORALS) survey has previously been used to demonstrate that the number density, gas and metals content of z>1.6 damped Lyman alpha systems is not significantly under-estimated in…

We present a detailed analysis of a very unusual sub-damped Lyman alpha (sub-DLA) system at redshift z=2.304 towards the quasar Q0453-423, based on high signal-to-noise (S/N), high-resolution spectral data obtained with VLT/UVES. With a…

We present the first results from our NASA Keck Observatory Database of Ionized Absorbers toward Quasars (KODIAQ) survey which aims to characterize the properties of the highly ionized gas of high redshift galaxies and their circumgalactic…

We present mid-infrared spectra and photometry from the Infrared Spectrograph on the Spitzer Space Telescope for 51 OH megamasers (OHMs), along with 15 galaxies confirmed to have no megamaser emission above L_OH = 10^2.3 L_sun. The majority…

In an effort to study Damped Lyman Alpha galaxies at low redshift, we have been using the Sloan Digital Sky Survey to identify galaxies projected onto QSO sightlines and to characterize their optical properties. For low redshift galaxies,…

We present findings of the detection of Magnesium II (Mg II, {\lambda} = 2796, 2803 {\AA}) absorbers from the early data release of the Dark Energy Spectroscopic Instrument (DESI). DESI is projected to obtain spectroscopy of approximately 3…

We study the multi-phase circumgalactic medium (CGM) of emission line galaxies (ELGs) at $z\sim1.5$, traced by MgII$\lambda2796$, $\lambda2803$ and CIV$\lambda1548$, $\lambda1550$ absorption lines, using approximately 7,000 ELG-quasar pairs…

We present a tomographic analysis of metal absorption lines arising from the circumgalactic medium (CGM) of galaxies at z~0.5-2, using Multi Unit Spectroscopic Explorer (MUSE) observations of two background quasars at z~2.2 and 2.8, which…

(Abridged) We use a high-resolution spectrum of the quasar HE0001-2340 observed with the UVES/VLT to measure Mg isotope abundances in the intervening absorption-line systems at high redshifts. Line profiles are prepared accounting for…

The exact nature of weak MgII absorbers (those with W_r(2796) < 0.3 A) is a matter of debate, but most are likely related to areas of local star formation or supernovae activity outside of giant galaxies. Using 18 QSO spectra obtained with…