J/ApJ/818/30 Lag measurements for 15 z<0.8 QSOs from the SDSS-RM (Shen+, 2016)
The Sloan Digital Sky Survey reverberation mapping project: first broad-line
Hβ and Mg II lags at z ≳ 0.3 from six-month spectroscopy.
Shen Y., Horne K., Grier C.J., Peterson B.M., Denney K.D., Trump J.R.,
Sun M., Brandt W.N., Kochanek C.S., Dawson K.S., Green P.J., Greene J.E.,
Hall P.B., Ho L.C., Jiang L., Kinemuchi K., McGreer I.D., Petitjean P.,
Richards G.T., Schneider D.P., Strauss M.A., Tao C., Wood-Vasey W.M.,
Zu Y., Pan K., Bizyaev D., Ge J., Oravetz D., Simmons A.
<Astrophys. J., 818, 30 (2016)>
=2016ApJ...818...30S 2016ApJ...818...30S (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Spectroscopy ; Surveys
Keywords: black hole physics; galaxies: active; line: profiles;
quasars: general; surveys
Abstract:
Reverberation mapping (RM) measurements of broad-line region (BLR)
lags in z>0.3 quasars are important for directly measuring black hole
masses in these distant objects, but so far there have been limited
attempts and success given the practical difficulties of RM in this
regime. Here we report preliminary results of 15 BLR lag measurements
from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM)
project, a dedicated RM program with multi-object spectroscopy
designed for RM over a wide redshift range. The lags are based on the
2014 spectroscopic light curves alone (32 epochs over six months) and
focus on the Hβ and Mg II broad lines in the 100 lowest-redshift
(z<0.8) quasars included in SDSS-RM; they represent a small subset of
the lags that SDSS-RM (including 849 quasars to z∼4.5) is expected to
deliver. The reported preliminary lag measurements are for
intermediate-luminosity quasars at 0.3≲z<0.8, including nine Hβ
lags and six Mg II lags, for the first time extending RM results to
this redshift-luminosity regime and providing direct quasar black hole
mass estimates over approximately half of cosmic time. The Mg II lags
also increase the number of known Mg II lags by several fold and start
to explore the utility of Mg II for RM at high redshift. The location
of these new lags at higher redshifts on the observed BLR
size-luminosity relationship is statistically consistent with previous
Hβ results at z<0.3. However, an independent constraint on the
relationship slope at z>0.3 is not yet possible owing to the
limitations in our current sample. Our results demonstrate the general
feasibility and potential of multi-object RM for z>0.3 quasars.
Description:
The spectroscopic data were taken during seven dark/gray runs from
2014 January to July and consist of a total of 32 epochs with an
average cadence of ∼4 days; each epoch had a typical exposure time of
2hr. The spectroscopic data were pipeline-processed as part of the
SDSS-III Data Release 12 (Alam et al. 2015ApJS..219...12A 2015ApJS..219...12A). The
wavelength coverage of BOSS spectroscopy is ∼3650-10400Å, with a
spectral resolution of R∼2000.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 156 15 Basic properties of the lag detections
table2.dat 69 479 Continuum and broad-line light curves
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See also:
J/ApJ/811/91 : SDSS-RM project: z<1 QSO host galaxies (Matsuoka+, 2015)
J/ApJ/806/22 : SEAMBHs IV. Hβ time lags (Du+, 2015)
J/ApJ/805/96 : SDSS-RM project: velocity dispersions of QSOs (Shen+, 2015)
J/ApJS/217/26 : Lick AGN monitoring 2011: light curves (Barth+, 2015)
J/ApJS/216/4 : SDSS-RM project: technical overview (Shen+, 2015)
J/ApJ/782/45 : SEAMBHs. I. Mrk 142, Mrk 335, and IRAS F12397+3333 (Du+, 2014)
J/ApJ/779/109 : Long-term monitoring of NGC 5548 (Peterson+, 2013)
J/ApJ/755/60 : Reverberation mapping for 5 Seyfert 1 galaxies (Grier+, 2012)
J/ApJ/732/121 : V-band and Hβ monitoring of Z299-15 (Barth+, 2011)
J/ApJ/716/993 : LAMP: reverberation mapping of H and He lines (Bentz+, 2010)
J/ApJ/680/169 : SDSS DR5 virial black hole masses (Shen+, 2008)
J/ApJ/613/682 : AGN central masses & broad-line region sizes (Peterson+, 2004)
http://www.sdss3.org/ : SDSS-III home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- RMID [101/840] Object index in full
SDSS-RM sample (1)
5- 22 A18 --- SDSS SDSS designation;
(HHMMSS.ss+DDMMSS.s; J2000)
24- 29 F6.4 --- z [0.1/0.8] SDSS-DR12 spectroscopic
redshift
31- 38 A8 --- Morph Morphological classification from
SDSS imaging ("extended" or "point")
40- 46 A7 --- Line Broad line used for lag detection
48- 51 I4 km/s sigrms [743/2824] Broad-line dispersion of
Line; second moment (2)
53- 54 I2 km/s e_sigrms The 1σ uncertainty in sigrms
56- 59 F4.1 d tau [10/37] Rest-frame time lag (3)
61- 64 F4.1 d e_tau Lower 1σ uncertainty in tau
66- 69 F4.1 d E_tau Upper 1σ uncertainty in tau
71- 75 F5.3 [Msun] logVP [6.1/7.8] Log virial product defined
in Equ. 5 (4)
77- 81 F5.3 [Msun] e_logVP Lower 1σ uncertainty in logVP
83- 87 F5.3 [Msun] E_logVP Upper 1σ uncertainty in logVP
89- 93 F5.3 10-17cW/m2/nm F5100 [0.1/7.1] Observed continuum flux at
rest-frame 5100 Angstroms (5)
95- 99 F5.3 10-17cW/m2/nm e_F5100 The 1σ uncertainty in F5100
101-106 F6.3 [10-7W] logL5100 [42.97/44.42] Log continuum luminosity
at rest-frame 5100 Angstroms (6)
108-112 F5.3 [10-7W] e_logL5100 The 1σ uncertainty in logL5100
114-117 F4.2 --- fhost [0/0.8] Host of total fraction in 5100
Angstrom continuum luminosity (7)
119-122 I4 km/s FWHMHb [1888/5923] Hβ broad-line FWHM
from mean spectrum
124-126 I3 km/s e_FWHMHb Uncertainty in FWHMHb
128-132 F5.3 [Msun] logMSE [7.5/8.6] Log single-epoch black hole
mass estimate (8)
134-138 F5.3 [Msun] e_logMSE The 1σ uncertainty in logMSE
140-143 I4 km/s sigmean [838/3283] Broad-line dispersion for
Line (9)
145-146 I2 km/s e_sigmean The 1σ uncertainty in sigmean
148-151 I4 km/s FWHMl [1661/5120] Broad-line FWHM for
Line (10)
153-156 I4 km/s e_FWHMl The 1σ uncertainty in FWHMl
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Note (1): Described in Shen et al. (2015, J/ApJS/216/4).
Note (2): Measured by PrepSpec using the RMS spectrum.
Note (3): From the centroid of the CCF peak.
Note (4): Which can be converted to the RM-based BH mass
logMRM=logVP+log(f) with f=5.5 adopted in this work.
Note (5): Host-corrected. Measured from spectral fits to the mean spectrum.
In 1e-17erg/s/cm2/A.
Note (6): Host-corrected. In erg/s.
Note (7): Estimated using a spectral decomposition approach
(Shen et al. 2015, J/ApJ/805/96).
Note (8): Based on the Hβ FWHM and continuum luminosity measured
from the mean spectrum, using the formula from
Vestergaard & Peterson (2006ApJ...641..689V 2006ApJ...641..689V).
Note (9): Measured by PrepSpec using the mean spectrum.
Note (10): Measured by PrepSpec using the RMS spectrum.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- RMID [101/840] Object index in full SDSS-RM sample (1)
5- 13 F9.3 d MJD Modified Julian Date
15- 26 E12.6 --- Fcont [0.4/15.2] Continuum flux (2)
28- 39 E12.6 --- e_Fcont [0.004/0.4] Uncertainty in fcont (3)
41- 52 E12.6 --- Fline [2.3/72.7] Broad-line flux in Line (2)
54- 65 E12.6 --- e_Fline [0.1/3.5] Uncertainty in fline (3)
67 I1 --- Mask [0/1] Mask code (0=used in the CCF analysis)
69 I1 --- Line [1/2] Broad-line code (1=Mg II or 2=Hβ)
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Note (1): Described in Shen et al. (2015, J/ApJS/216/4).
Note (2): Derived from spectroscopy using PrepSpec (Section 2.1), and the
continuum is always estimated at rest-frame 5100 Angstroms. Flux
units are arbitrary. See Table 1 for basic properties of each object.
Note (3): The errors on the LCs are the original PrepSpec output, while we have
used inflated 3% fractional errors in the LCs in our CCF analysis
(see Section 2.2 for details).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 22-Apr-2016