J/ApJ/641/78 CIV variability in 105 SDSS quasars (Wilhite+, 2006)
Spectral variability of quasars in the Sloan Digital Sky Survey.
II. The C IV line.
Wilhite B.C., Vanden Berk D.E., Brunner R.J., Brinkmann J.V.
<Astrophys. J., 641, 78-89 (2006)>
=2006ApJ...641...78W 2006ApJ...641...78W
ADC_Keywords: Active gal. nuclei ; QSOs
Keywords: galaxies: active - quasars: general - techniques: spectroscopic
Abstract:
We examine the variability of the high-ionization CIV λ1549
line in a sample of 105 quasars observed at multiple epochs by the
Sloan Digital Sky Survey. We find a strong correlation between the
change in the CIV line flux and the change in the line width, but no
correlations between the change in flux and changes in line center and
skewness. The relation between line flux change and line width change
is consistent with a model in which a broad line base varies with
greater amplitude than the line core. The objects studied here are
more luminous and at higher redshift than those normally studied for
variability, ranging in redshift from 1.65 to 4.00 and in absolute
r-band magnitude from roughly -24 to -28.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 66 105 CIV variability sample
table2.dat 27 105 CIV flux variability
table3.dat 43 105 CIV profile variability
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See also:
J/ApJ/633/638 : 315 SDSS variable quasar sample (Wilhite+, 2005)
J/A+A/321/123 : Optical variability of QSOs (Cristiani+ 1997)
J/A+AS/143/465 : Quasar variability (Hawkins+, 2000)
J/AJ/131/1923 : Known quasars in the QUEST Variability Survey
(Rengstorf+, 2006)
J/MNRAS/268/305 : Variability of optically selected quasars (Hook+ 1994)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source running number
5- 22 A18 --- SDSS SDSS name (HHMMSS.ss+DDMMSS.s) (1)
24- 28 I5 d MJDH Modified Julian date of the high-S/N epoch
30- 34 I5 d MJDL Modified Julian date of the low-S/N epoch
36- 39 F4.2 --- z High-S/N epoch redshift
41- 45 F5.1 d Dtau Rest-frame time lag
47- 50 F4.1 mag Rmag High-S/N apparent R band magnitude
52- 56 F5.1 mag RMAG High-S/N absolute R band magnitude
58- 61 F4.1 --- S/NH The S/N of the high-S/N epoch
63- 66 F4.1 --- S/NL The S/N of the low-S/N epoch
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Note (1): SDSS JHHMMSS.ss+DDMMSS.s in Simbad.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source running number
5- 8 F4.1 10-19W/m2/nm FcontH High-S/N continuum flux (1)
10- 13 F4.1 10-19W/m2/nm FcontL Low-S/N continuum flux (1)
15- 20 F6.1 10-19W/m2/nm FlineH High-S/N line flux (1)
22- 27 F6.1 10-19W/m2/nm FlineL Low-S/N line flux (1)
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Note (1): In units of 10-17erg/s/cm2/Angstrom.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Source running number
5- 11 F7.2 0.1nm lambdaH High-S/N median wavelength (1)
13- 19 F7.2 0.1nm lambdaL Low-S/N median wavelength (1)
21- 25 F5.1 0.1nm EqWH ? High-S/N line width (1)
27- 31 F5.1 0.1nm EqWL ? Low-S/N line width (1)
33- 37 F5.2 --- PskewH ? High-S/N Pearson skewness value
39- 43 F5.2 --- PskewL ? Low-S/N Pearson skewness value
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Note (1): In units of Angstroms.
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History:
From electronic version of the journal
References:
Wilhite et al., Paper I 2005ApJ...633..638W 2005ApJ...633..638W, Cat. <J/ApJ/633/638
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 27-Jul-2007