J/MNRAS/354/L31 SDSS DR2 QSO and DLA properties (Murphy+, 2004)
Dust-reddening and gravitational lensing of SDSS QSOs due to foreground
damped Lyman α systems.
Murphy M.T., Liske J.
<Mon. Not. R. Astron. Soc., 354, L31-L36 (2004)>
=2004MNRAS.354L..31M 2004MNRAS.354L..31M
ADC_Keywords: QSOs ; Redshifts ; Equivalent widths
Keywords: dust, extinction - galaxies: high-redshift - intergalactic medium -
galaxies: ISM - quasars: absorption line
Abstract:
We use Sloan Digital Sky Survey (SDSS) Data Release 2 quasi-stellar
object (QSO) spectra to constrain the dust-reddening caused by
intervening damped Lyman α systems (DLAs). Comparing the
spectral index distribution of a 70 sight-line DLA sample with that of
a large control sample reveals no evidence for dust-reddening at z∼3.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 97 1979 Catalogue of DR2 QSO and DLA properties.
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See also:
J/AJ/126/2579 : SDSS quasar catalog. First data release (Schneider+, 2003)
J/MNRAS/354/L25 : MgII absorbers in SDSS QSOs (Bouche+, 2004)
http://www.sdss.org/dr2 : SDSS-DR2 Home Page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- SDSS SDSS J2000 name of the QSO derived from the RA
and DEC supplied in the FITS headers of the
spectra (HHMMSS.ss+DDMMSS.s)
20- 25 F6.4 --- z SDSS emission redshift of the QSO given in the
FITS headers of the spectra.
27- 32 F6.3 mag r'mag r'-band PSF magnitude corrected for
Galactic extinction
34- 39 F6.3 mag i'mag i'-band PSF magnitude corrected for
Galactic extinction
41- 46 F6.3 mag z'mag z'-band PSF magnitude corrected for
Galactic extinction
48- 53 F6.3 --- Sp+Index Spectral index.
55- 59 F5.3 --- e_Sp+Index 1-sigma statistical error in spectral index
61- 65 F5.2 --- S/Nmin Minimum signal-to-noise ratio
67- 72 F6.4 ---- zabs ?=0.0000 Absorption redshift of the DLA
(approximate only)
74- 79 F6.3 0.1nm EWHa ?=0.000 Rest-frame equivalent width of the
damped Lyman alpha line
82- 86 F5.3 0.1nm e_EWHa ?=0.000 1-sigma statistical error in EWHa
88 I1 --- DLA [0/2] Status of DLA detection (1)
91 I1 --- Target [0/1] Primary (1) or secondary (0) SDSS target
94 I1 --- DR1 [0/1] QSO appears (1) or did not appears (0)
in SDSS DR1 QSO catalogue
(Cat. J/AJ/126/2579)
97 I1 --- BAL [0/1] QSO deemed (1) or not deemed (0)
to have BALs (2)
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Note (1): Damped Lymanα (DLA) detection flags as follows:
0 = indicates no DLA detected
1 = indicates that the DLA detection is plausible, though
unconvincing and so is excluded from further analysis (i.e. this
sight-line appears in neither the DLA or control samples)
2 = indicates that the DLA detection is taken to be genuine
Note (2): Flag indicating whether the QSO was judged, by visual inspection, to
have some moderately strong Broad Absorption Lines (BALs) in its
spectrum.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Apr-2005