J/ApJS/221/7 SDSS QSOs at z<0.8. II. New spectroscopic obs. (Runnoe+, 2015)
A large systematic search for close supermassive binary and rapidly recoiling
black holes.
II. Continued spectroscopic monitoring and optical flux variability.
Runnoe J.C., Eracleous M., Mathes G., Pennell A., Boroson T.,
Sigurosson S., Bogdanovic T., Halpern J.P., Liu J.
<Astrophys. J. Suppl. Ser., 221, 7 (2015)>
=2015ApJS..221....7R 2015ApJS..221....7R (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Velocity dispersion ; Redshifts ; Spectroscopy ;
Equivalent widths
Keywords: atlases; galaxies: active; quasars: general
Abstract:
We present new spectroscopic observations that are part of our
continuing monitoring campaign of 88 quasars at z<0.7 whose broad
Hβ lines are offset from their systemic redshifts by a few
thousand km/s. These quasars have been considered as candidates for
hosting supermassive black hole binaries (SBHBs) by analogy with
single-lined spectroscopic binary stars. We present the data and
describe our improved analysis techniques, which include an extensive
evaluation of uncertainties. We also present a variety of measurements
from the spectra that are of general interest and will be useful in
later stages of our analysis. Additionally, we take this opportunity
to study the variability of the optical continuum and integrated flux
of the broad Hβ line. We compare the variability properties of
the SBHB candidates to those of a sample of typical quasars with
similar redshifts and luminosities observed multiple times during the
Sloan Digital Sky Survey. We find that the variability properties of
the two samples are similar (variability amplitudes of 10%-30% on
timescales of approximately 1-7 years) and that their structure
functions can be described by a common model with parameters
characteristic of typical quasars. These results suggest that the
broad-line regions of SBHB candidates have a similar extent as those
of typical quasars. We discuss the implications of this result for the
SBHB scenario and the ensuing constraints on the orbital parameters.
Description:
The selection process and spectroscopic properties of the sample of
supermassive black hole binary (SBHB) candidates are described in
detail in Paper I (Eracleous+, 2012, J/ApJS/201/23).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 95 212 Log of Spectroscopic Observations
table3.dat 112 328 Spectral measurements for broad Hβ
table4.dat 87 328 Spectral measurements for [OIII]λ5007
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See also:
VII/270 : SDSS quasar catalog: tenth data release (Paris+, 2014)
J/ApJ/799/72 : Binary AGNs from the VLA Stripe 82 survey (Fu+, 2015)
J/ApJ/779/109 : Long-term monitoring of NGC 5548 (Peterson+, 2013)
J/ApJ/777/64 : A search for double-peaked AGNs in AGES (Comerford+, 2013)
J/ApJ/769/95 : [NeV] or [NeIII] double peaked SDSS quasars (Barrows+, 2013)
J/MNRAS/426/1701 : High-frequency QPO in black hole binaries (Belloni+, 2012)
J/ApJS/201/31 : Emission-line galaxies from SDSS. I. (Ge+, 2012)
J/ApJS/201/23 : Spectroscopy of 88 z<0.7 SDSS QSOs (Eracleous+, 2012)
J/ApJ/753/42 : Double-peaked AGN. I. Dual AGN candidates (Comerford+, 2012)
J/ApJ/746/L22 : Dual AGNs in the nearby Universe (Koss+, 2012)
J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)
J/AJ/140/390 : Karhunen-Loeve transform of SDSS QSOs (Boroson+, 2010)
J/ApJ/716/866 : SDSS search for binary AGN (Smith+, 2010)
J/ApJ/708/427 : Type 2 AGNs with double-peaked [OIII] lines (Liu+, 2010)
J/ApJ/705/L76 : AGNs with double-peaked [OIII] lines (Wang+, 2009)
J/A+A/417/515 : I Zw 1 unusual emission line spectrum (Veron-Cetty+, 2004)
J/ApJ/599/886 : Emission lines of radio-loud AGN (Eracleous+, 2003)
J/AJ/126/1720 : ugriz and Hα of double-peaked AGN (Strateva+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
6- 24 A19 --- SDSS Object SDSS name (JHHMMSS.ss+DDMMSS.s)
26- 31 F6.4 --- z [0.07/0.8] Spectroscopic redshift (1)
33- 37 F5.2 mag Vmag [15.8/19.9] Apparent V band magnitude (2)
39- 43 F5.3 mag Av [0.02/0.7] Galactic visual extinction
in V band (3)
45- 50 F6.2 mag VMag [-26.3/-21.2] Absolute V band magnitude (4)
52- 53 I2 --- No [2/17] Total number of observations (5)
55- 64 A10 "Y/M/D" Date ? UT date of the observation
66 A1 --- Flag [hN] Observation flag (6)
68- 69 A2 --- Instr Instrument code (7)
71- 74 I4 s Exp [480/7200]? Exposure time
76- 78 I3 --- S/N [3/134]? Signal-to-Noise (8)
80- 83 I4 0.1nm lam1 [2462/4628]? Lower rest-frame wavelength range
85- 88 I4 0.1nm lam2 [3869/8824]? Upper rest-frame wavelength range
90- 95 I06 --- ID [001224/180545] Abbreviated object SDSS
identifier (as in tables 3 and 4;
column added by CDS)
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Note (1): As measured in this paper from the peak wavelength
of [OIII]λ5007 line.
Note (2): Determined from the SDSS PSF magnitudes, as described in
Section 4.1 of Paper I (Eracleous+, 2012, J/ApJS/201/23).
Note (3): Taken from Schlegel, Finkbeiner, & Davis (1998ApJ...500..525S 1998ApJ...500..525S).
Note (4): Computed as described in Section 2.1 of the text.
Note (5): Includes those reported in Paper I (Eracleous+, 2012, J/ApJS/201/23).
Note (6): Flag as follows:
h = Average of two spectra taken within a few days of each other. The
exposure time is the sum of the individual exposure times and the date
is the "median" of the dates of the two observations.
N = No new observations.
Note (7): See Table 2 for full details. Code as follows:
MM = MDM, Hiltner 2.4m, MODSPEC spectrograph;
MO = MDM, Hiltner 2.4m, OSMOS spectrograph;
K = KPNO, Mayall 4m, Ritchie-Cretien spectrograph;
Ab = APO, ARC 3.5m, Double Imaging Spectrograph, blue arm;
Ar = APO, ARC 3.5m, Double Imaging Spectrograph, red arm;
H2 = Hobby-Eberly Telescope, Low-Resolution Spectrograph, G2 grism;
H3 = Hobby-Eberly Telescope, Low-Resolution Spectrograph, G3 grism.
Note (8): In the continuum near the line of interest. When the spectrum
includes the Hβ line we give the S/N in the continuum near
this line, at 4600Å. If the spectrum includes only the
MgIIλ2800 line, we give the S/N in the continuum near this
line, at 2900 AA. Some of the APO spectra cover the continuum
between the above lines but neither of the lines themselves; for
these spectra we report the S/N in the continuum at 3600Å.
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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- 6 I06 --- ID [001224/180545] Abbreviated object SDSS
identifier
8- 17 A10 "Y/M/D" Date ? UT date of the observation
19- 23 I5 km/s FWHM [1900/19800] Full-Width at Half-Maximum
25- 28 I4 km/s e_FWHM [60/4000] Uncertainty in FWHM
30- 34 I5 km/s FWQM Full-Width at Quarter-Maximum
36- 39 I4 km/s e_FWQM Uncertainty in FWQM
41- 45 I5 km/s PShift [-5900/6800] Peak velocity shift
47- 50 I4 km/s e_PShift [30/1000] Uncertainty in PShift
52- 56 I5 km/s CShift Centroid velocity shift
58- 60 I3 km/s e_CShift Uncertainty in Shift
62- 65 I4 km/s sigma [1100/9500] Velocity dispersion
67- 69 I3 km/s e_sigma [20/900] Uncertainty in sigma
71- 76 F6.3 --- Skew [-0.2/0.4] Pearson skewness coefficient
78- 82 F5.3 --- e_Skew [0.008/0.06] Uncertainty in Skew
84- 87 F4.2 --- Kurt [2.1/5.5] Kurtosis coefficient
89- 92 F4.2 --- e_Kurt [0.03/0.3] Uncertainty in Kurt
94- 98 I5 10-17mW/m2 Flux [45/32000] Integrated flux (broad Hβ)
100-103 I4 10-17mW/m2 e_Flux [2/2000] Uncertainty in Integrated Flux
105-108 I4 0.1nm EW [8/2000] Equivalent width
110-112 I3 0.1nm e_EW [1/200] Uncertainty in EW
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I06 --- ID [001224/180545] Abbreviated object SDSS
identifier
8- 17 A10 "Y/M/D" Date ? UT date of the observation
19- 23 F5.1 10-17cW/m2/nm F5100 [0.1/673] Flux density at 5100 Angstroms
25- 27 F3.1 10-17cW/m2/nm e_F5100 [0.1/0.3] Uncertainty in F5100
29- 32 I4 km/s FWHM [200/1100] FWHM Full-Width at
Half-Maximum (1)
34- 36 I3 km/s sigma [100/800] Velocity dispersion
38- 42 I5 km/s e_sigma [7/20000] Uncertainty in sigma
44- 48 F5.2 --- Skew [-0.3/0.4] Pearson skewness coefficient
50- 53 F4.2 --- e_Skew [0.01/0.2] Uncertainty in Skew
55- 58 F4.2 --- Kurt [2.4/9.8] Kurtosis coefficient
60- 63 F4.2 --- e_Kurt [0.01/0.4] Uncertainty in Kurt
65- 69 I5 10-17mW/m2 Flux [20/10000] Integrated flux
([OIII]λ5007)
71- 74 I4 10-17mW/m2 e_Flux [1/1000] Uncertainty in Flux
76- 81 F6.1 0.1nm EW [3/1300] Equivalent width
83- 87 F5.1 0.1nm e_EW [0.2/200] Uncertainty in EW
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Note (1): Uncertainties are less than 70km/s.
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History:
From electronic version of the journal
References:
Eracleous et al. Paper I. 2012ApJS..201...23E 2012ApJS..201...23E Cat. J/ApJS/201/23
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Jan-2016