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More confirmed damped Lyman-Alpha systems from the Las Campanas/Palomar surveyWe present moderate-resolution spectra of six high-redshift quasars which contain nine candidate damped Lyman alpha absorption systems identified in the Las Campanas/Palomar survey of Lanzetta et al. (ApJS, 77, 1 (1991)). Eight of the nine candidate damped Lyman alpha absorption systems are confirmed (one tentative), including seven with N(H I) greater than or equal to 2 x 10(exp 20) /sq cm. The remaining one turns out to be due to blending of many narrow absorption lines. Accurate absorption redshifts, H I column densities, and metal-line equivalent widths are provided for these systems in order to facilitate future studies of detailed physical condition and chemical abundances. We briefly discuss the 18 other metal-line systems identified along these sight lines. The z(sub abs) = 2.6527 system toward Q 2231-00 is interesting in that it shows strong O VI (lambda) (lambda) 1031, 1037 absorption. The O VI ion is one of the best diagnostics of hot gas, and high resolution studies of the O VI absorption is likely to yield important clues regarding the ionization mechanism of the metal-line systems. Another system, at z(sub abs) = 2.3771 toward Q 2239-38, shows relatively strong Zn II and Cr II absorption, clearly indicating that it belongs to the same class absorbers as the damped Lyman systems. We have not obtained metal abundances for this system because the H(sub I) column density is not available. We also find a Lyman limit absorption system at z(sub abs)= 3.5090 toward Q 2239-38 which does not show obvious metal absorption lines. More sensitive observations are required to check on this interesting possibility.
Document ID
19950029861
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Lu, Limin
(Univ. of Wisconsin, Madison, WI United States)
Wolfe, Arthur M.
(Univ. of California, La Jolla, CA United States)
Date Acquired
August 16, 2013
Publication Date
July 1, 1994
Publication Information
Publication: The Astronomical Journal
Volume: 108
Issue: 1
ISSN: 0004-6256
Subject Category
Astrophysics
Accession Number
95A61460
Funding Number(s)
CONTRACT_GRANT: NAGW-2119
CONTRACT_GRANT: NAS5-26555
Distribution Limits
Public
Copyright
Other

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