scispace - formally typeset
Open AccessJournal ArticleDOI

The Low-luminosity End of the Radius-Luminosity Relationship for Active Galactic Nuclei

TLDR
In this article, the authors present an updated and revised analysis of the relationship between the H{beta} broadline region (BLR) radius and the luminosity of the active galactic nucleus (AGN).
Abstract
We present an updated and revised analysis of the relationship between the H{beta} broad-line region (BLR) radius and the luminosity of the active galactic nucleus (AGN). Specifically, we have carried out two-dimensional surface brightness decompositions of the host galaxies of nine new AGNs imaged with the Hubble Space Telescope Wide Field Camera 3. The surface brightness decompositions allow us to create ''AGN-free'' images of the galaxies, from which we measure the starlight contribution to the optical luminosity measured through the ground-based spectroscopic aperture. We also incorporate 20 new reverberation-mapping measurements of the H{beta} time lag, which is assumed to yield the average H{beta} BLR radius. The final sample includes 41 AGNs covering four orders of magnitude in luminosity. The additions and updates incorporated here primarily affect the low-luminosity end of the R{sub BLR}-L relationship. The best fit to the relationship using a Bayesian analysis finds a slope of {alpha}= 0.533{sup +0.035}{sub -0.033}, consistent with previous work and with simple photoionization arguments. Only two AGNs appear to be outliers from the relationship, but both of them have monitoring light curves that raise doubt regarding the accuracy of their reported time lags. The scatter around the relationship is found to be 0.19more » {+-} 0.02 dex, but would be decreased to 0.13 dex by the removal of these two suspect measurements. A large fraction of the remaining scatter in the relationship is likely due to the inaccurate distances to the AGN host galaxies. Our results help support the possibility that the R{sub BLR}-L relationship could potentially be used to turn the BLRs of AGNs into standardizable candles. This would allow the cosmological expansion of the universe to be probed by a separate population of objects, and over a larger range of redshifts.« less

read more

Citations
More filters
Journal ArticleDOI

Swift/UVOT grism monitoring of NGC 5548 in 2013: an attempt at MgII reverberation mapping

TL;DR: In this article, the authors performed reverberation mapping using MgII in the well-studied nearby Seyfert 1, NGC 5548, to estimate high-redshift black hole masses.
Journal ArticleDOI

Spectropolarimetry of Seyfert 1 galaxies with equatorial scattering: black hole masses and broad-line region characteristics

TL;DR: In this article, the spectropolarimetric observations of a sample of 30 Type 1 AGNs and an analysis of the observed polarization in these AGNs have been performed with the 6-meter telescope of SAO RAS using the modified SCORPIO-2 spectropholarimeter.
Journal ArticleDOI

Supermassive black holes with high accretion rates in active galactic nuclei. XI. Accretion disk reverberation mapping of Mrk 142

TL;DR: In this paper, the authors performed an intensive accretion disk reverberation mapping campaign on the high accretion rate active galactic nucleus Mrk 142 in early 2019 and measured significant time lags between the different wavelength light curves, finding that through the UV and optical the wavelength-dependent lags, τ(λ), generally follow the relation τ (λ)∝λ4/3, as expected for theT∝R−3/4profile of a steady-state optically-thick, geometrically-thin disk, though can also be fit by τ
Journal ArticleDOI

Correlated X-ray/ultraviolet/optical variability in NGC 6814

TL;DR: The LT is operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council.
References
More filters
Journal ArticleDOI

Maps of Dust Infrared Emission for Use in Estimation of Reddening and Cosmic Microwave Background Radiation Foregrounds

TL;DR: In this article, a reprocessed composite of the COBE/DIRBE and IRAS/ISSA maps, with the zodiacal foreground and confirmed point sources removed, is presented.
Journal ArticleDOI

Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds

TL;DR: In this paper, the authors presented a reprocessed composite of the COBE/DIRBE and IRAS/ISSA maps, with the zodiacal foreground and confirmed point sources removed.
Book

Numerical Recipes in FORTRAN

TL;DR: The Diskette v 2.04, 3.5'' (720k) for IBM PC, PS/2 and compatibles [DOS] Reference Record created on 2004-09-07, modified on 2016-08-08.
Journal ArticleDOI

Measuring Reddening with Sloan Digital Sky Survey Stellar Spectra and Recalibrating SFD

TL;DR: In this paper, the authors measured the difference between the measured and predicted colors of a star, as derived from stellar parameters from the Sloan Extension for Galactic Understanding and Exploration Stellar Parameter Pipeline, and achieved uncertainties of 56, 34, 25, and 29 mmag in the colors u − g, g − r, r − i, and i − z, per star.
Journal ArticleDOI

Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD

TL;DR: Lee et al. as discussed by the authors measured the difference between the measured and predicted colors of a star, as derived from stellar parameters from the SEGUE Stellar Parameter Pipeline, and achieved uncertainties of 56, 34, 25, and 29 mmag in the colors u-g, g-r, r-i, and i-z, per star.
Related Papers (5)