J/ApJ/944/29 Reverberation mapping of IC 4329A (Bentz+, 2023)
Reverberation mapping of IC 4329A.
Bentz M.C., Onken C.A., Street R., Valluri M.
<Astrophys. J., 944, 29 (2023)>
=2023ApJ...944...29B 2023ApJ...944...29B
ADC_Keywords: Spectra, optical; Photometry; Galaxies, nearby;
Active gal. nuclei
Keywords: Reverberation mapping ; Seyfert galaxies ; Supermassive black holes
Abstract:
We present the results of a new reverberation mapping campaign for the
broad-line active galactic nucleus (AGN) in the edge-on spiral
IC4329A. Monitoring of the optical continuum with V-band photometry
and broad emission-line flux variability with moderate-resolution
spectroscopy allowed emission-line light curves to be measured for
Hβ, Hγ, and HeIIλ4686. We find a time delay of
16.3-2.3+2.6 days for Hβ, a similar time delay of
16.0-2.6+4.8 days for Hγ, and an unresolved time delay of
-0.6-3.9+3.9 days for HeII. The time delay for Hβ is
consistent with the predicted value from the relationship between AGN
luminosity and broad-line region radius, after correction for the
∼2.4mag of intrinsic extinction at 5100Å. Combining the measured
time delay for Hβ with the broad emission-line width and an
adopted value of =4.8, we find a central supermassive black hole
mass of MBH=6.8-1.1+1.2x107M☉. Velocity-resolved time
delays were measured across the broad Hβ emission-line profile
and may be consistent with an "M"-like shape. Modeling of the full
reverberation response of Hβ was able to provide only modest
constraints on some parameters, but does exhibit agreement with the
black hole mass and average time delay. The models also suggest that
the AGN structure is misaligned by a large amount from the edge-on
galaxy disk. This is consistent with expectations from the unified
model of AGNs, in which broad emission lines are expected to be
visible only for AGNs that are viewed at relatively face-on
inclinations.
Description:
Photometric monitoring of IC 4329A was carried out with the Las
Cumbres Observatory (LCO) 1.0m telescope network under the program
NSF-2022A-012 (PI: Bentz). Observations began on 2022 February 3 (UT)
and continued throughout the 2022A semester, ending on 2022 July 31. A
60s V-band image was scheduled to occur every ∼8hr using the Sinistro
imaging cameras, providing a 26.5'x26.5' field of view and an angular
scale of 0.389"/pix.
Over the course of the semester, a total of 374 images were acquired
from the LCO facilities at three sites --164 from Cerro Tololo
Interamerican Observatory (CTIO), 138 from the South African
Astronomical Observatory (SAAO), and 72 from Siding Spring Observatory
(SSO)-- with a median (average) time sampling of 0.35 (0.47) days.
Spectroscopic monitoring with the FLOYDS spectrographs on the 2.0m
Faulkes Telescopes North and South was carried out under programs
NSF-2022A-012 and ANU-2022A-002. The FLOYDS spectrographs are
cross-dispersed instruments providing wavelength coverage of
540-1000nm with a dispersion of 3.51Å/pix in the first order, and
wavelength coverage of 320-570nm with a dispersion of 1.74Å/pix in
the second order. Observations began on 2022 March 7 and were
scheduled every ∼24hr through 2022 July 31. Over the course of the
semester, 45 spectra (23 from FTN and 22 from FTS) were acquired with
a median (average) time sampling of 2.0 (3.2) days.
Objects:
---------------------------------------------------------------
RA (ICRS) DE Designation(s) (z)
---------------------------------------------------------------
13 49 19.26 -30 18 34.2 IC 4329A = ESO 445-50 (z=0.01605)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 67 91 Continuum and emission-line light curves
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See also:
II/179 : Southern Spectrophotometric Standards. I + II (Hamuy+ 1992,94)
VII/110 : Rich Clusters of Galaxies (Abell+ 1989)
J/MNRAS/327/265 : SMAC. III. Fundamental Plane catalog (Hudson+, 2001)
J/AJ/128/1761 : HATNET variability survey (Hartman+, 2004)
J/ApJ/613/682 : AGN masses and broad-line region sizes (Peterson+, 2004)
J/ApJ/666/674 : ESSENCE supernova survey (Miknaitis+, 2007)
J/A+A/542/A83 : CAIXA. II. AGNs from excess variance analysis (Ponti+, 2012)
J/ApJ/761/123 : KELT-1 photometry and spectroscopy follow-up (Siverd+, 2012)
J/ApJ/779/109 : Long-term monitoring of NGC 5548 (Peterson+, 2013)
J/ApJ/806/128 : Space telescope RM project. I. NGC5548 (De Rosa+, 2015)
J/ApJ/821/56 : Space telescope RM project. III. LCs (Fausnaugh+, 2016)
J/MNRAS/463/3813 : ASASSN-15oi UBVI M2W1W2 light curves (Holoien+, 2016)
J/ApJ/840/97 : Optical RM campaign of 5 AGNs (Fausnaugh+, 2017)
J/ApJ/837/131 : Space telescope RM project. V. NGC5548 sp. (Pei+, 2017)
J/ApJ/905/77 : Monitoring AGNs with Hb Asymmetry. II. (Brotherton+, 2020)
J/ApJS/262/14 : AGNs with Hβ asymmetry. III. 15 PG quasars (Bao+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.4 d HJDcont [9615.1/9791.1] Heliocentric Julian
date, continuum; HJDcont-2450000
11- 15 F5.3 10-15cW/m2/nm FV [2/3] LCO/Sinistro V-band flux density
in 10-15erg/s/cm2/Å
17- 21 F5.3 10-15cW/m2/nm e_FV [0.01/0.1] FV uncertainty
23- 31 F9.4 d HJDem [9646/9786]? Heliocentric Julian date,
emission lines; HJDem-2450000
33- 37 F5.3 10-13mW/m2 FHb [2.19/3.2]? Hβ integrated flux in
10-13erg/s/cm2
39- 43 F5.3 10-13mW/m2 e_FHb [0.01/0.06]? FHb uncertainty
45- 49 F5.3 10-13mW/m2 FHg [0.38/0.72]? Hγ integrated flux
in 10-13erg/s/cm2
51- 55 F5.3 10-13mW/m2 e_FHg [0.008/0.05]? FHg uncertainty
57- 61 F5.3 10-13mW/m2 FHeII [0.1/0.75]? HeII integrated flux in
10-13erg/s/cm2
63- 67 F5.3 10-13mW/m2 e_FHeII [0.01/0.06]? FHeII uncertainty
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Jan-2025