Reverberation Mapping of the Kepler-Field AGN KA1858+4850

Abstract

KA1858+4850 is a narrow-line Seyfert 1 galaxy at redshift 0.078 and is among the brightest active galaxies monitored by the Kepler mission. We have carried out a reverberation mapping campaign designed to measure the broad-line region size and estimate the mass of the black hole in this galaxy. We obtained 74 epochs of spectroscopic data using the Kast Spectrograph at the Lick 3-m telescope from February to November of 2012, and obtained complementary V-band images from five other ground-based telescopes. We measured the H-beta light curve lag with respect to the V-band continuum light curve using both cross-correlation techniques (CCF) and continuum light curve variability modeling with the JAVELIN method, and found rest-frame lags of lag_CCF = 13.53 (+2.03, -2.32) days and lag_JAVELIN = 13.15 (+1.08, -1.00) days. The H-beta root-mean-square line profile has a width of sigma_line = 770 +/- 49 km/s. Combining these two results and assuming a virial scale factor of f = 5.13, we obtained a virial estimate of M_BH = 8.06 (+1.59, -1.72) x 10^6 M_sun for the mass of the central black hole and an Eddington ratio of L/L_Edd ~ 0.2. We also obtained consistent but slightly shorter emission-line lags with respect to the Kepler light curve. Thanks to the Kepler mission, the light curve of KA1858+4850 has among the highest cadences and signal-to-noise ratios ever measured for an active galactic nucleus; thus, our black hole mass measurement will serve as a reference point for relations between black hole mass and continuum variability characteristics in active galactic nuclei.

References in corpus (6)

• Modeling the Time Variability of SDSS Stripe 82 Quasars as a Damped Random Walk
• Supermassive black holes with high accretion rates in active galactic nuclei: I. First results from a new reverberation mapping campaign
• The Black Hole Mass Scale of Classical and Pseudo Bulges in Active Galaxies
• On the variability of quasars: a link between Eddington ratio and optical variability?
• The dependence of quasar variability on black hole mass
• Investigating Active Galactic Nuclei Variability Using Combined Multi-Quarter Kepler Data

Cited by in corpus (29)

• Space Telescope and Optical Reverberation Mapping Project. III. Optical Continuum Emission and Broad-Band Time Delays in NGC 5548
• Unification of the Fundamental Plane and Super-Massive Black Holes Masses
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$\beta$ Time Lags and Implications for Super-Eddington Accretion
• The Lick AGN Monitoring Project 2011: Spectroscopic Campaign and Emission-Line Light Curves
• The Radius-Luminosity Relationship Depends on Optical Spectra in Active Galactic Nuclei
• A characteristic optical variability timescale in astrophysical accretion disks
• Velocity-resolved reverberation mapping of five bright Seyfert 1 galaxies
• Rotation in the Pleiades With K2: III. Speculations on Origins and Evolution
• Can reverberation-measured quasars be used for cosmology?
• On the multi-wavelength variability of Mrk 110: Two components acting at different timescales
• Current and future applications of Reverberation-mapped quasars in Cosmology
• Simultaneous Kepler/K2 and XMM-Netwon observations of superflares in the Pleiades
• Test of the Formation mechanism of the Broad Line Region in Active Galactic Nuclei
• Stability of the Broad Line Region Geometry and Dynamics in Arp 151 Over Seven Years
• A New Approach to the Internal Calibration of Reverberation Mapping Spectra
• Do reverberation-measured H$\beta$ quasars provide a useful test of cosmology?
• A new method to measure the virial factors in the reverberation mapping of AGNs
• An extended size-luminosity relation for the reverberation-mapped AGNs: the role of the accretion rate
• High Eddington quasars as discovery tools: current state and challenges
• Kepler light curve analysis of the blazar W2R 1926+42
• The supermassive black hole masses of reverberation-mapped active galactic nuclei
• Anomalous Broad-Line Region Responses to Continuum Variability in Active Galactic Nuclei. I. H$\beta$ Variability
• Robotic Reverberation Mapping of Arp 151
• Reverberation Mapping of PG 0934+013 with the Southern African Large Telescope
• Measuring the Virial Factor in SDSS DR5 Quasars with Redshifted H$\beta$ and Fe ii Broad Emission Lines
• Measuring the Virial Factor in SDSS DR7 AGNs with Redshifted H$\beta$ and H$\alpha$ Broad Emission Lines
• Dust Reverberation Mapping and Light-Curve Modelling of Zw229-015
• Multi-epoch X-ray spectral analysis of Centaurus A: revealing new constraints on iron emission line origins
• OzDES Reverberation Mapping Program: Stacking analysis with H$\beta$, Mg II and C IV