J/MNRAS/454/3962 188 CIV BAL QSOs from SDSS DR7 (He+, 2015)
Variability of QSOs with variable regions in broad absorption troughs from the
Sloan Digital Sky Survey.
He Z.-C., Bian W.-H., Ge X., Jiang X.-L.
<Mon. Not. R. Astron. Soc., 454, 3962-3976 (2015)>
=2015MNRAS.454.3962H 2015MNRAS.454.3962H (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Spectroscopy ; Equivalent widths
Keywords: galaxies: active - galaxies: nuclei - quasars: absorption lines
Abstract:
The variability of broad absorption lines (BALs) is investigated for a
sample of 188 BAL quasars (QSOs) (z>1.7) with at least two epoch
observations from the Sloan Digital Sky Survey Data Release 7,
covering a time-scale of about 0.001-3yr in the rest frame.
Considering only the longest time-scale between epochs for each QSO,
73 variable regions in the CIV BAL troughs are detected for 43 BAL
QSOs. The proportion of BAL QSOs showing variable regions increases
with longer time-interval than about 1 yr in the rest frame. The
velocity width of variable regions is narrow compared to the
BAL-trough outflow velocity. For 43 BAL QSOs with variable regions, it
is found that there is a medium strong correlation between the
variation of the continuum luminosity at 1500Å and the variation of
the spectral index. With respect to the total 188 QSOs, a larger
proportion of BAL QSOs with variable regions appears bluer during
their brighter phases, which implies that the origin of BAL variable
regions is related to the central accretion process. For 43 BAL QSOs
with variable regions, it is possible that there is a negative medium
strong correlation between the absolute variation of the equivalent
width and the Mgii-based black hole mass, and a medium strong
correlation between the maximum outflow velocity of variable regions
and the Eddington ratio. These results imply a connection between the
BAL-trough variation and the central accretion process.
Description:
In the SDSS DR7, it is found that there are 1080 spectra of 480 CIV
BAL QSOs with at least two-epoch observations. In order to identify
the variable regions in CIV BAL troughs, we select BAL QSOs with SDSS
spectral signal-to-noise ratio (S/N) at r band larger than 10, and
redshift more than 1.7. It consists of 188 CIV BAL QSOs with 428 SDSS
spectra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 85 376 The properties of 188 BAL QSOs
table3.dat 157 43 The subsample of 43 two-epoch spectra with
identified variable BAL regions
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See also:
J/A+A/427/107 : Polarization in BAL QSOs (Lamy+, 2004)
J/ApJS/165/1 : BAL QSOs from SDSS DR3 (Trump+, 2006)
J/ApJ/665/990 : SDSS DR2 BAL QSOs (Ganguly+, 2007)
J/ApJ/692/758 : BAL QSOs in SDSS-DR5 (Gibson+, 2009)
J/ApJ/696/924 : UV and X-Ray radio-quiet QSOs (Gibson+, 2009)
J/MNRAS/410/860 : Redshift dependence of BAL QSOs (Allen+, 2011)
J/MNRAS/427/1135 : Properties of radio-loud BAL quasars (DiPompeo+, 2012)
J/MNRAS/444/2498 : Radio-Quiet BAL quasars sample (Rochais+, 2014)
J/MNRAS/449/1593 : CIV absorption in BAL QSOs (Baskin+, 2015)
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 Sequential number of BAL QSO
5- 6 I2 --- Ep Epoch number
8- 26 A19 --- SDSS SDSS name (JHHMMSS.ss+DDMMSS.s)
28- 32 F5.3 --- z Redshift
34- 48 A15 --- PMF SDSS Plate-MJD-Fibre of the observation
50- 56 F7.2 10+34W/nm L1500 Luminosity (in 10+40erg/s/Å)
58- 63 F6.2 10+34W/nm e_L1500 rms uncertainty on L1500
65- 69 F5.2 --- alpha UV spectral index
71- 74 F4.2 --- e_alpha rms uncertainty on alpha
76- 80 F5.2 0.1nm EWCIV Total CIV BAL equivalent width
82- 85 F4.2 0.1nm e_EWCIV rms uncertainty on EWCIV
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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 --- N Sequential number of the two-epoch spectra
5- 23 A19 --- SDSS SDSS Name (JHHMMSS.ss+DDMMSS.s)
25- 29 F5.3 --- z Redshift
31- 45 A15 --- PMF1 Plate-MJD-fibre of one observation
47- 61 A15 --- PMF2 Plate-MJD-fibre of another observation
63- 67 F5.2 [10-7W] logLbol Bolometric luminosity
69- 73 F5.2 [Msun] logMBH ?=- MgII-based black hole mass
75- 78 F4.2 [Msun] e_logMBH ? rms uncertainty on logMBH
80- 83 F4.2 --- Lbol/LEdd ?=- Eddington ratio
85- 90 F6.2 0.1nm DEW EW difference (ΔEW) of all variable
BAL regions in two-epoch different spectra
92- 95 F4.2 0.1nm e_DEW rms uncertainty on DEW
97-103 F7.1 km/s Vmax1 First boundary of all variable BAL
regions maximum velocity
105-111 F7.1 km/s Vmin1 First boundary of all variable BAL
regions minimum velocity
113-119 F7.1 km/s Vmax2 ? Second boundary of all variable BAL
regions maximum velocity
121-127 F7.1 km/s Vmin2 ? Second boundary of all variable BAL
regions minimum velocity
129-135 F7.1 km/s Vmax3 ? Third boundary of all variable BAL
regions maximum velocity
137-143 F7.1 km/s Vmin3 ? Third boundary of all variable BAL
regions minimum velocity
145-150 F6.1 km/s Vmax4 ? Fourth boundary of all variable BAL
regions maximum velocity
152-157 F6.1 km/s Vmin4 ? Fourth boundary of all variable BAL
regions minimum velocity
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 22-Jul-2016