J/ApJS/236/39 CIV narrow absorption line systems in SDSS-DR14 (Chen+, 2018)
The correlated variations of CIV narrow absorption lines and quasar continuum.
Chen Z.-F., Pang T.-T., He B., Huang Y.
<Astrophys. J. Suppl. Ser., 236, 39 (2018)>
=2018ApJS..236...39C 2018ApJS..236...39C
ADC_Keywords: QSOs; Spectra, optical; Redshifts; Equivalent widths
Keywords: galaxies: active ; galaxies: halos ; methods: data analysis ;
quasars: absorption lines
Abstract:
We assemble 207 variable quasars from the Sloan Digital Sky Survey,
all with at least 3 observations, to analyze CIV narrow absorption
doublets, and obtain 328 CIV narrow absorption line systems. We find
that 19 out of 328 CIV narrow absorption line systems were changed by
|ΔWrλ1548|≥3σΔWrλ1548 on
timescales from 15.9 to 1477 days at rest-frame. Among the 19
obviously variable CIV systems, we find that (1) 14 systems have
relative velocities υr>0.01c and 4 systems have
υr>0.1c, where c is the speed of light; (2) 13 systems are
accompanied by other variable CIV systems; (3) 9 systems were changed
continuously during multiple observations; and (4) 1 system with
υr=16862km/s was enhanced by
ΔWrλ1548=2.7σΔWrλ1548 in 0.67
day at rest-frame. The variations of absorption lines are inversely
correlated with the changes in the ionizing continuum. We also find
that large variations of CIV narrow absorption lines are form
differently over a short timescale.
Description:
We select quasars from the DR14Q catalog (Paris+ 2018A&A...613A..51P 2018A&A...613A..51P),
all with three- to six-epoch observations. The purpose of this paper
is to analyze the variation of CIV narrow absorption lines (NALs), so
in our sample we only consider quasars with zem>1.32. Then, we
download the quasar spectra from http://data.sdss.org/sas/dr14/.
Among the 207 quasars, there are 166 quasars that at least one CIV NAL
system with Wrλ1548≥3σWrλ1548 and
Wrλ1551≥2σWrλ1551 was detected in one of
the multi-epoch spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 105 2420 Catalog of CIV narrow absorption line systems for
166 SDSS quasars
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See also:
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
VII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)
J/ApJ/613/129 : Equivalent widths of QSOs (Wise+, 2004)
J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)
J/ApJ/708/427 : Type 2 AGNs with double-peaked [OIII] lines (Liu+, 2010)
J/ApJ/769/95 : [NeV] or [NeIII] double peaked SDSS quasars (Barrows+, 2013)
J/ApJ/777/168 : CIV & SiIV broad absorption line troughs (Filiz+, 2013)
J/MNRAS/434/163 : QSOs narrow absorption line variability (Hacker+, 2013)
J/ApJS/210/7 : BOSS narrow CIV absorption lines. I. zem≤2.4 (Chen+, 2014)
J/ApJS/215/12 : BOSS narrow CIV absorption lines. II. zem>2.4 (Chen+, 2014)
J/MNRAS/450/3904 : Quasars narrow absorption lines from SDSS (Chen+, 2015)
J/MNRAS/454/3962 : 188 CIV BAL QSOs from SDSS DR7 (He+, 2015)
J/ApJ/814/150 : Variability of SDSS broad absorption line QSOs (Wang+, 2015)
J/MNRAS/463/24 : AGNs with double-peaked narrow emission lines (Lyu+, 2016)
J/ApJ/825/25 : NALs of lensed QSO J1029+2623 (Misawa+, 2016)
J/MNRAS/462/3285 : XQ-100 targets equivalent widths (Perrotta+, 2016)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Pair [1/1210] Identification number
of CIV NAL-pairs
6- 23 A18 --- SDSS SDSS object name
(HHMMSS.ss+DDMMSS.s; J2000)
25- 29 I5 --- Plate [268/10000] SDSS plate number
31- 35 I5 --- MJD [51633/57519] SDSS Modified Julian Date
37- 40 I4 --- Fiber [1/1000] SDSS fiberID
42- 47 F6.4 --- zem [1.3/4.3] Emission line redshift of
the quasar
49- 54 F6.4 --- zabs [1.3/4.3] Absorption line redshift of
the CIV NAL system
56- 59 F4.2 0.1nm EW1548 [0.04/4.2] Rest frame equivalent width,
CIV 1548Å
61- 64 F4.2 0.1nm e_EW1548 [0.01/1] Uncertainty in EW1548
66- 69 F4.2 0.1nm EW1551 [0.03/3.8] Rest frame equivalent width,
CIV 1551Å
71- 74 F4.2 0.1nm e_EW1551 [0.02/1] Uncertainty in EW1551
76- 82 F7.3 10-19W/m2/nm F1350 [0.3/104] 1350Å continuum flux
from the original SDSS spectra;
in 10-17erg/s/cm2/Å units
84- 88 F5.3 10-19W/m2/nm e_F1350 [0.2/6.2] Uncertainty for F1350
90- 94 I5 km/s vr [-1564/49631] Velocity offset, CIV NAL
system with respect to the quasar
emission line redshift
96- 98 I3 --- ID [1/328] Identification number of
the CIV NAL system
100-101 I2 --- Flag [-2/2]? Flag (1)
103-105 F3.1 --- SL [0/6]? Significance level of
the variation (2)
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Note (1): Flag as follows:
1 = enhanced CIV NALs with |dWr(1548A)|≥3*σWr(1548A);
-1 = weakened CIV NALs with |dWr(1548A)|≥3*σWr(1548A);
2 = emerged CIV NALs;
-2 = disappeared CIV NALs;
0 = CIV NALs with |dWr(1548A)|<3*σWr(1548A).
See Equations 4 and 5 for the calculations of dWr(1548A)
and σWr(1548A).
Note (2): The significance level (SL) of the variation is equated to
|dWr(1548A)|/σWr(1548A). Note that, if the rest frame equivalent
widths and corresponding errors of both lines of a CIV doublet are same,
these values are the 1σ upper limits of absorption strengths and
indicate that the CIV NALs are not observed in the corresponding spectra.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 31-Aug-2018