J/ApJS/243/2 SiIV and NV absorption line SDSS quasar systems (Chen+, 2019)
The correlated variations of absorption lines and quasar continuum.
Chen Z.-F., Yi S.-X., Pang T.-T., Yi T.-F., Wang Z.-W., Mo X.-H., Liu C.-Q.
<Astrophys. J. Suppl. Ser., 243, 2-2 (2019)>
=2019ApJS..243....2C 2019ApJS..243....2C (SIMBAD/NED BibCode)
ADC_Keywords: Equivalent widths; QSOs; Redshifts; Spectra, optical
Keywords: catalogs; galaxies: halos; quasars: absorption lines; quasars: general
Abstract:
Using the quasar spectra from the Sloan Digital Sky Survey and with
variable C IV absorption line systems, we measure the Si IV and N V
absorption line systems. We obtain 50 variable Si IV absorption line
systems and 39 variable N V absorption line systems. We find that the
variations in most of the C IV, Si IV, and N V absorption lines are
correlated with the changes in quasar continuum. In addition, a
significant portion of the variable absorption lines are the
consistent variations of multiple systems with large velocity
separations. Therefore, the variations of the C IV, Si IV, and N V
absorption lines could be mainly driven by the changes in quasar
radiations, which cause changes in ionization states or column
densities of absorbing gas. We also find that the variable C IV, Si
IV, and N V absorption line systems can be divided into low-ionization
systems and high-ionization systems. The former positively responds to
the changes in the quasar's brightness, and the later is the
oppositive case.
Description:
Using Data Release 14 (DR14; Paris+ 2018A&A...613A..51P 2018A&A...613A..51P) of the SDSS,
Chen+ (2018, J/ApJS/239/23) selected the quasars with two- to
six-epoch observations to measure the CIV absorption lines with FWHMs
<1200km/s in the vicinity of CIV emission lines and obtained 647
variable CIV absorption line systems from the SDSS spectra of 553
quasars. These SDSS spectra of the 553 quasars are utilized to measure
the SiIVλ1393,1402 or NVλ1238,1242 absorption lines.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
qsos.dat 25 322 List of SDSS quasars from Tables 1 and 2;
table added by CDS
table1.dat 103 716 Catalog of SiIV Absorption Line Systems
table2.dat 103 584 Catalog of NV Absorption Line Systems
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See also:
VII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)
J/ApJS/171/1 : Census of QSOs Narrow Absorption Lines (Misawa+, 2007)
J/ApJ/777/168 : CIV and SiIV BAL troughs in SDSS (Filiz+, 2013)
J/MNRAS/450/3904 : Quasars narrow absorption lines from SDSS (Chen+, 2015)
J/ApJ/814/150 : Variability of SDSS broad absorption line QSOs (Wang+, 2015)
J/ApJ/818/30 : Lag measurements for 15 z<0.8 QSOs from SDSS-RM (Shen+, 2016)
J/ApJ/843/30 : MgII line vs 3000Å continuum analysis in 68 QSOs
J/ApJS/236/39 : CIV NAL systems in SDSS-DR14 (Chen+, 2018)
J/ApJ/856/6 : SEAMBHs IX. 10 new Hβ light curves (Du+, 2018)
J/ApJ/862/22 : CIV BAL SDSS QSO obs. with Gemini (Rogerson+, 2018)
J/ApJS/239/23 : CIV NAL systems from SDSS-DR14 quasar spectra (Chen+, 2018)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: qsos.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- SDSS SDSS object name (HHMMSS.ss+DDMMSS.s; J2000)
20- 25 F6.4 --- zem [1.7/4.5] Quasar redshift
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Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 3 I3 --- Pair [1/358] ID number of a NAL pair
5- 22 A18 --- SDSS SDSS object name
(HHMMSS.ss+DDMMSS.s; J2000)
24- 27 I4 --- Plate SDSS spectra plate ID
29- 33 I5 d MJD SDSS spectra modified Julian Date
of observation
35- 37 I3 --- Fiber SDSS spectra fiber ID
39- 44 F6.4 --- zem [1.75/4.26] Redshift, quasar
46- 51 F6.4 --- zabs [1.73/4.14] Redshift, absorption line
system, blue line of the SiIV doublet
53- 56 F4.2 0.1nm EW1393 [0.05/4] Equivalent width at rest frame,
SiIV 1393Å
58- 61 F4.2 0.1nm e_EW1393 [0/0.6] Uncertainty in EW1393 (1)
63- 66 F4.2 0.1nm EW1402 [0.04/3.8] Equivalent width at rest
frame, SiIV 1402Å
68- 71 F4.2 0.1nm e_EW1402 [0/0.7] Uncertainty in EW1402 (1)
73- 79 F7.3 10-19W/m2/nm F1350 [6/422] Continuum 1350Å flux, rest
frame; in 10-17erg/s/cm2/Å units
81- 85 F5.3 10-19W/m2/nm e_F1350 [0.2/5] Uncertainty in flux1350
87- 91 I5 km/s Vr [-4498/28417] Offset velocity, SiIV
absorption line system to quasar
redshift (G1)
93- 95 I3 --- ID [1/295] Identification number of the SiIV
absorption line system
97- 98 I2 --- Sys [-2/2]? System category (2)
100-103 F4.1 --- SL [0/17.4]? Significance level of the
variation (3)
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Note (1): Note that, if the equivalent widths at rest frame and
corresponding errors of both lines of a Si IV doublet are the same,
these values are the 1 σ upper limits of absorption strengths and
manifest that the Si IV absorption line systems are not observed in the
corresponding spectra.
Note (2): System category as follows:
0 = systems with |EW1393|<3*(e_EW1393);
-1 = weakened systems with |EW1393|≥3*(e_EW1393);
1 = enhanced systems with |EW1393|≥3*(e_EW1393);
-2 = disappeared systems;
2 = emerged systems.
Note (3): The significance level (SL) of the variation, which is the ratio
|EW1393|/e_EW1393
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Pair [1/292] Identification number of a NAL pair
5- 22 A18 --- SDSS SDSS object name
(HHMMSS.ss+DDMMSS.s; J2000)
24- 27 I4 --- Plate SDSS spectra plate ID
29- 33 I5 d MJD SDSS spectra modified Julian Date
of observation
35- 37 I3 --- Fiber SDSS spectra fiber ID
39- 44 F6.4 --- zem [1.95/4.45] Redshift, quasar
46- 51 F6.4 --- zabs [1.90/4.37] Redshift, absorption line
system, blue line of the NV doublet
53- 56 F4.2 0.1nm EW1238 [0.1/3.3] Equivalent width at rest frame,
NV1238Å
58- 61 F4.2 0.1nm e_EW1238 [0.02/0.5] Uncertainty in EW1238 (1)
63- 66 F4.2 0.1nm EW1242 [0.09/3.3] Equivalent width at rest frame,
NV1242Å
68- 71 F4.2 0.1nm e_EW1242 [0.01/0.5] Uncertainty in EW1242 (1)
73- 79 F7.3 10-19W/m2/nm F1350 [2.5/291] Continuum flux, rest frame,
1350Å; in 10-17erg/s/cm2/Å units
81- 85 F5.3 10-19W/m2/nm e_F1350 [0.2/3] Uncertainty in flux1350
87- 91 I5 km/s Vr [-4382/5445] Offset velocity, NV absorption
line system to quasar redshift (G1)
93- 95 I3 --- ID [1/257] Identification number of the
NV absorption line system
97- 98 I2 --- Sys [-1/1]? System category (2)
100-103 F4.1 --- SL [0/13.1]? Significance level of the
variation (3)
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Note (1): Note that, if the equivalent widths at rest frame and
corresponding errors of both lines of a N V doublet are the same,
these values are the 1 σ upper limits of absorption strengths and
manifest that the N V absorption line systems are not observed in the
corresponding spectra.
Note (2): System category as follows:
0 = systems with |EW1238|<3*(e_EW1238);
-1 = weakened systems with |EW1238|≥3*(e_EW1238);
1 = enhanced systems with |EW1238|≥3*(e_EW1238);
-2 = disappeared systems;
2 = emerged systems.
Note (3): The significance level (SL) of the variation, which is the ratio
|EW1238|/e_EW1238
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Global notes:
Note (G1):
Vr=((1+zem)2-(1+zabs)2)/((1+zem)2+(1+zabs)2)*c, where
the c is the speed of light
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-Dec-2019