J/AJ/159/259 Opt-NIR light curve of the quasar 3C 273 (Sobrino Figaredo+, 2020)
Dust reverberation of 3C 273: Torus structure and lag-luminosity relation.
Sobrino Figaredo C., Haas M., Ramolla M., Chini R., Blex J., Hodapp K.W.,
Murphy M., Kollatschny W., Chelouche D., Kaspi S.
<Astron. J., 159, 259 (2020)>
=2020AJ....159..259S 2020AJ....159..259S
ADC_Keywords: QSOs; Photometry, ugriz; Photometry, infrared
Keywords: Reverberation mapping ; Active galactic nuclei ; Photometry ; Quasars
Abstract:
We monitored the z=0.158 quasar 3C273 between 2015 and 2019 in the
optical (BVrz) and near-infrared (JHK) with the aim to perform dust
reverberation mapping. Accounting for host galaxy and accretion disk
contributions, we obtained pure dust light curves in JHK. Cross
correlations between the V-band and the dust light curves yield an
average rest-frame delay for the hot dust of τcent∼410days. This
is a factor of two shorter than that expected from the the dust ring
radius Rx∼900lt-day reported from interferometric studies. The dust
covering factor (CF) is about 8%, much smaller than that predicted
from the half covering angle of 45° found for active galactic
nuclei (AGNs). We analyze the asymmetric shape of the correlation
functions and explore whether an inclined biconical bowl-shaped dust
torus geometry could bring these findings (τcent, Rx and CF) into
a consistent picture. The hot varying dust emission originates from
the edge of the bowl rim with a small covering angle
40°<θ<45°, and we see only the near side of the biconus.
Such a dust gloriole with Rx= 900±200lt-day and an inclination
12° matches the data remarkably well. Comparing the results of
3C273 with literature for less luminous AGN, we find a lag-luminosity
relation τ∝Lα with α=0.33-0.40, flatter than the
widely adopted relation with α∼0.5. We address several
explanations for the new lag-luminosity relation.
Description:
3C273 was observed between 2015-April and 2019-June with semi-robotic
optical and near infrared (NIR) telescopes of the Bochum University
Observatory near Cerro Armazones (OCA) in Chile. The optical
telescopes used are: the 40cm Bochum Monitoring Telescope (BMT), the
15cm Robotic Bochum Twin Telescope ROBOTT (formerly named VYSOS 6, for
short V6), the 25cm BEST-II, and the 80cm infrared telescope IRIS.
The light curves were created using 5-10 nearby (<30') calibration
stars. The optical and NIR absolute flux calibration was performed by
comparison with the PANSTARSS and the 2MASS catalog, respectively;
also, airmass-dependent extinction and Galactic foreground extinction
corrections were applied.
Objects:
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RA (2000) DE Designation(s)
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12 29 06.70 +02 03 08.6 3C273 = Gaia DR2 3700386905605055360
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
figure1.dat 32 579 3C 273 normalized light curves
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)
J/A+A/506/569 : BEST-II periodic variables in CoRoT LRa02 field (Kabath+,2009)
J/AN/333/706 : Bochum survey of the southern Galactic disk (Haas+, 2012)
J/ApJ/756/73 : gri light curves of low-luminosity AGN NGC 4395 (Edri+, 2012)
J/ApJ/788/159 : 17 Seyfert 1 galaxies light curves (Koshida+, 2014)
J/A+A/561/L8 : BRJK photometry of Seyfert galaxy WPVS48 (Pozo Nunez+, 2014)
J/ApJS/213/26 : Optical light curves of PHL1811 and 3C273 (Fan+, 2014)
J/ApJS/217/26 : Lick AGN monitoring 2011: light curves (Barth+, 2015)
J/ApJ/825/126 : SEAMBHs. V. The third year (Du+, 2016)
J/ApJ/846/98 : Jet kinematics of blazars at 43GHz with VLBA (Jorstad+, 2017)
J/ApJS/229/21 : VRI monitoring of the QSO 3C 273 in 2005-2016 (Xiong+, 2017)
J/MNRAS/465/L114 : OGLE16aaa UVOT light curves (Wyrzykowski+, 2017)
J/A+A/620/A137 : CCD B,V,R,I,Ha photometry of 3C120 (Ramolla+, 2018)
J/ApJ/854/107 : Light curves of 2 Seyfert 1 galaxies (Fausnaugh+, 2018)
J/ApJ/856/6 : SEAMBHs IX. 10 new Hβ light curves (Du+, 2018)
J/ApJ/866/133 : Continuum-Hβ light curves of 5 Seyfert 1 (De Rosa+, 2018)
J/ApJ/871/108 : Lick AGN monitoring project 2011: V band (Pancoast+, 2019)
J/ApJS/245/25 : WISE Extended Source Catalog (WXSC). I. (Jarrett+, 2019)
Byte-by-byte Description of file: figure1.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Filt Filter used (B, V, r, z, Jn, Hn, Ks)
4- 11 A8 --- Tel Telescope used (1)
13- 21 F9.3 d MJD [57134/58622] Modified Julian Date
23- 27 F5.2 mJy Flux [21.2/82.9] Observed flux in Filter
29- 32 F4.2 mJy e_Flux [0/2.93] Uncertainty in Flux
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Note (1): Telescopes as follows:
BMT = the 40cm Bochum Monitoring Telescope;
IRIS = the 80 cm infrared telescope IRIS;
VYSOS6_a = the "a" portion of the 5cm Robotic Bochum Twin Telescope ROBOTT;
VYSOS6_b = the "b" portion of the 5cm Robotic Bochum Twin Telescope ROBOTT;
best2 = the 25cm BEST-II telescope.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 20-Jul-2020