The Magellan uniform survey of damped Lyman α systems – II. Paucity of strong molecular hydrogen absorption★
نویسندگان
چکیده
منابع مشابه
Molecular hydrogen and the nature of damped Lyman-α systems
We report results from our mini-survey for molecular hydrogen in eight high-redshift damped Lyman-α (DLA) systems using the ESO Ultra-violet and Visible Spectrograph on the VLT. In addition, we investigate two systems using ESO public data. We include in the sample the only system where H2 was previously detected and studied at high-spectral resolution. Altogether our sample consists of eleven ...
متن کاملThe VLT-UVES survey for molecular hydrogen in high-redshift damped Lyman-α systems⋆
We have searched for molecular hydrogen in damped Lyman-α (DLA) and subDLA systems at high redshift (zabs > 1.8) using UVES at the VLT down to a detection limit of typically N(H2) = 2×10 14 cm. Out of the 33 systems in our sample, 8 have firm and 2 have tentative detections of associated H2 absorption lines. Considering that 3 detections were already known from past searches, molecular hydrogen...
متن کاملMolecular hydrogen in high-redshift Damped Lyman-α systems: The VLT/UVES database
Aims. We present the current status of ongoing searches for molecular hydrogen in high-redshift (1.8 < zabs ≤ 4.2) Damped Lyman-α systems (DLAs) capitalising on observations performed with the ESO Very Large Telescope (VLT) Ultraviolet and Visual Echelle Spectrograph (UVES). Methods. We identify 77 DLAs/strong sub-DLAs, with log N(H i) ≥ 20 and zabs > 1.8, which have data that include redshifte...
متن کاملMetallicity Evolution of Damped Lyman-α Systems
According to Pei, Fall & Hauser (1999), the global metallicity evolution of the Universe can be represented by the ratio of the total metal content to the total gas content measured in Damped Lyman–α (DLA) systems (the “column density weighted metallicity” à la Pettini). To minimize dust obscuration effects, a DLA sample with negligible dust content is considered, namely, 50 DLAs with logNHI < ...
متن کاملNICMOS Snapshot Survey of Damped Lyman α Quasars
We image 19 quasars with 22 damped Lyman α (DLA) systems using the F160W filter and the Near-Infrared Camera and Multiobject Spectrograph aboard the Hubble Space Telescope, in both direct and coronagraphic modes. We reach 5σ detection limits of ∼H=22 in the majority of our images. We compare our observations to the observed Lyman-break population of high-redshift galaxies, as well as Bruzual & ...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2014
ISSN: 1365-2966,0035-8711
DOI: 10.1093/mnras/stu1314