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The Deuterium Abundance toward Q1937–1009
We present a new measurement of the deuterium-to-hydrogen ratio (D/H) in the Lyman limit absorption system at z = 3.572 toward Q1937-1009. Tytler, Fan & Burles (TFB) made the first extragalacticExpand
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The Deuterium abundance toward QSO 1009+2956
We present a measurement of the deuterium to hydrogen ratio (D/H) in a metal-poor absorption system at redshift z = 2.504 toward the QSO 1009+2956. We apply the new method of Burles & Tytler toExpand
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THE COSMOLOGICAL BARYON DENSITY FROM THE DEUTERIUM-TO-HYDROGEN RATIO IN QSO ABSORPTION SYSTEMS: D/H TOWARD Q1243+3047
We report the detection of deuterium absorption at redshift 2.525659 toward Q1243+3047. We describe improved methods to estimate the deuterium to hydrogen abundance ratio (D/H) in absorption systems,Expand
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The Distribution of QSO Absorption System Column Densities: Evidence for a Single Population
The distribution of H I column densities in a representative sample of all cosmologically distributed QSO absorption-line systems is examined. Remarkably, this distribution function f(N) is aExpand
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The Evolution of Lyman-alpha Absorbers in the Redshift Range 0.5 < z < 1.9
We investigate the evolution and the statistical properties of the Ly α absorbers of the intergalactic medium (IGM) in the largely unexplored redshift range z = 0.5−1.9. We use high-resolution (R ≥Expand
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Review of Big Bang Nucleosynthesis and Primordial Abundances
Big Bang Nucleosynthesis (BBN) is the synthesis of the light nuclei, Deuterium (D or 2H), 3He, 4He and 7Li during the first few minutes of the universe. This review concentrates on recentExpand
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The H I opacity of the intergalactic medium at redshifts 1.6 < z < 3.2
We use high-quality echelle spectra of 24 quasi-stellar objects to provide a calibrated measurement of the total amount of Lyα forest absorption (DA) over the redshift range 2.2 < z < 3.2. OurExpand
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r-Process Abundances and Chronometers in Metal-poor Stars
Rapid neutron-capture (i.e., r-process) nucleosynthesis calculations, employing internally consistent and physically realistic nuclear physics input (quasi-particle random-phase approximation (QRPA)Expand
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Intrinsic Properties of the ⟨z⟩ = 2.7 Lyα Forest from Keck Spectra of Quasar HS 1946+7658
We present the highest quality Ly? forest spectra published to date. We have complete 7.9 km s-1 FWHM spectra between the Ly? and Ly? emission lines of the bright, high-redshift (V = 15.9, z = 3.05)Expand
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Intergalactic HeII absorption towards QSO 1157+3143
We report the discovery of a further line of sight allowing detection of He  Lyα absorption by the intergalactic medium. A HST/STIS survey of 32 bright z ∼ 3 quasars selected from the HamburgExpand
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