We report on Hubble Space Telescope Faint Object Spectrograph observations of the double QSO HS 1216+5032 AB (ze(A) = 1.455; ze(B) = 1.451, and angular separation θ = 9. 1). The spectral coverage is 910 Å to 1340 Å in the QSO rest-frame. An unusual broadabsorption-line (BAL) system is observed only in the B component: maximum outflow velocity of ∼ 5 000 km s; probably a mixture of broad and nar...

We examine a large set of synthetic quasar spectra to realistically assess the potential of using the relative sizes of highly ionized near-zones in the Lyα and Lyβ forest as a probe of the neutral hydrogen content of the intergalactic medium (IGM) at z > 6. The scatter in the relative near-zone size distribution, induced by underlying fluctuations in the baryonic density field and the filterin...

We report the detection, based on HST and Keck data, of two peculiar absorbers in the Lyα forest of the quasar PKS 0454+039. These clouds, at redshifts z = 0.6248 and 0.9315 respectively, display both Mg ii and Fe ii absorption lines in addition to the Lyα line. Based upon photoionization models, these are inferred to be photoionized by the intergalactic UV background, and to have H i column de...

We present optical, infrared and radio data of the z = 4.11 radio galaxy TN J1338−1942 including an intermediate resolution spectrum obtained with FORS1 on the VLT Antu telescope. TN J1338−1942 was the first z > 4 radio galaxy to be discovered in the southern hemisphere and is one of the most luminous Lyα objects in its class. The Lyα and rest–frame optical emission appear co–spatial with the b...

We report on Hubble Space Telescope Faint Object Spectrograph observations of the double QSO HS 1216+5032 AB (ze(A) = 1.455; ze(B) = 1.451, and angular separation θ = 9. ′′1). The spectral coverage is 910 Å to 1340 Å in the QSO rest-frame. An unusual broad-absorption-line (BAL) system is observed only in the B component: maximum outflow velocity of ∼ 5 000 km s−1; probably a mixture of broad an...