activity
19962026
most citedSpace Telescope and Optical Reverberation Mapping Project. II. Swift and HST Reverberation Mapping of the Accretion Disk of NGC 5548

309 citations · 1k across the 41 of their papers we have counts for

collaborators

42 papers

astro-ph.GA2026

NGC 3227 Blinks: An Extreme Changing-Look Event in a Seyfert Galaxy

Kaiwen Zhang, Michael S. Brotherton, Pu Du +10

We report a rapid optical changing-look event in the Seyfert galaxy NGC 3227: the optical continuum faded by more than 70% and broad H-beta emission nearly disappeared within weeks…

astro-ph.HE2026

The unusually red delay spectrum of the low-mass black hole AGN NGC\,4051 as revealed by intensive continuum reverberation mapping with the Las Cumbres Observatory

Marcin Marculewicz, Juan V. Hernández Santisteban, Keith Horne +12

We present a two-year optical reverberation mapping campaign of NGC 4051, an active galactic nucleus (AGN) hosting a low-mass black hole (), using daily observ…

astro-ph.GA2026

First reverberation mapping of a Bowen fluorescence line

Martin W. Ochmann, Edward M. Cackett, Lukas Diehl +3

Reverberation mapping (RM) is a powerful tool to determine the extent, structure, and kinematics of the broad-line region (BLR) of active galactic nuclei (AGN). So far, RM of the B…

astro-ph.GA2026

A Phenomenological Study of the Accretion Disk in the Super-Eddington AGN I Zw 1

Farin Drewes, Roberta Vieliute, Juan V. Hernández Santisteban +11

The structure of the accretion disk in AGN is still an unsolved question, especially how it may change with Eddington ratio. Here we examine the accretion disk in the super-Eddingt…

astro-ph.GA2025

AGN STORM 2. XI. Spectroscopic reverberation mapping of the hot dust in Mrk 817

Hermine Landt, Benjamin D. Boizelle, Michael S. Brotherton +41

The AGN Space Telescope and Optical Reverberation Mapping 2 (STORM 2) campaign targeted Mrk 817 with intensive multi-wavelength monitoring and found its soft X-ray emission to be s…

astro-ph.HE2025

XRISM/Resolve Spectroscopy of the Central Engine in the Seyfert-1 AGN Mrk 279

Jon M. Miller, Xin Xiang, Doyee Byun +9

High-resolution X-ray spectroscopy with XRISM gives an unprecedented view of the ``central engine'' in active galactic nuclei, providing unique insights into black hole accretion a…

astro-ph.GA2025

The SDSS-V Black Hole Mapper Reverberation Mapping Project: Light Echoes of the Coronal Line Region in a Luminous Quasar

Theodore B. Smith, Logan B. Fries, Jonathan R. Trump +19

We present a reverberation mapping analysis of the coronal line [Ne V]3427 emitting region of the quasar COS168 (SDSS J095910.30+020732.2). [Ne V]3427 is known as one of the…

astro-ph.HE2025

The Accretion Disk Size Problem in AGN Disk Reverberation Mapping is an Obscuration Effect: A Uniform AGN Sample Study with Swift

Collin Lewin, Erin Kara, Christos Panagiotou +5

In the past decade, Swift has performed several AGN high-cadence reverberation mapping campaigns, and generally found that the UV/optical interband lags are 3 times longer th…

astro-ph.GA2025

Departures from Standard Disk Predictions in Intensive Ground-Based Monitoring of Three AGN

Diego Gonzalez-Buitrago, Aaron J. Barth, Rick Edelson +42

We present ground-based, multi-band light curves of the AGN Mrk~509, NGC\,4151, and NGC\,4593 obtained contemporaneously with \sw\, monitoring. We measure cross-correlation lags re…

astro-ph.GA2025

Continuum Reverberation Mapping of Accretion Disks Surrounding Supermassive Black Hole Binaries: Observational Signatures

Yi-Xin Fu, Yan-Rong Li, Jian-Min Wang +9

It has remained challenging to reliably identify sub-parsec supermassive black hole binaries (SMBHBs), despite them being expected to be ubiquitous. We propose a new method using m…

astro-ph.GA2025

Echo mapping of the black hole accretion flow in NGC 7469

Raj Prince, Juan V. Hernández Santisteban, Keith Horne +20

Reverberation mapping (RM) can measure black hole accretion disc sizes and radial structure through observed time lags that should increase with wavelength as . Ou…

astro-ph.IM2025

PyTICS: An Iterative Method for Photometric Lightcurve Intercalibration using Comparison Stars

Roberta Vieliute, Juan V. Hernández Santisteban, Keith Horne +1

Intensive reverberation mapping monitoring programs combine ground-based photometric observations from different telescopes, requiring intercalibration of lightcurves to reduce sys…

astro-ph.HE2025★ 3 cited

Testing X-ray Reprocessing and Mapping the Soft Excess of NGC 7469 with NICER

Ethan R. Partington, Edward M. Cackett, Rick Edelson +5

We present an X-ray/UV reverberation analysis of NGC 7469 across 210 days, using daily NICER observations with contemporaneous monitoring by Swift UVOT+XRT. We model the X-ray spec…

astro-ph.GA2025

Monitoring AGNs with H Asymmetry. V. Long-term Variation and Evolution of the Broad H Emission-Line Profiles

Feng-Na Fang, Pu Du, Michael S. Brotherton +40

The physical origins of the diverse emission-line asymmetries observed in the spectra of active galactic nuclei (AGNs) remain incompletely understood. Monitoring the temporal varia…

astro-ph.GA2025★ 3 cited

Accretion disc reverberation mapping of the quasar 3C 273

James P. Thorne, Hermine Landt, Jiamu Huang +5

We present accretion disc size measurements for the well-known quasar 3C 273 using reverberation mapping (RM) performed on high-cadence light-curves in seven optical filters collec…

astro-ph.HE2025

Testing disc reprocessing models for AGN optical variability by comparison of X-ray and optical power spectra of NGC 4395

Max Beard, Ian McHardy, Keith Horne +11

It is generally thought that AGN optical variability is produced, at least in part, by reprocessing of central X-rays by a surrounding accretion disc, resulting in wavelength-depen…

astro-ph.GA2024

The Sloan Digital Sky Survey Reverberation Mapping Project: Insights on Maximizing Efficiency in Lag Measurements and Black-Hole Masses

Y. Homayouni, Yuanzhe Jiang, W. N. Brandt +8

Multi-year observations from the Sloan Digital Sky Survey Reverberation Mapping (SDSS-RM) project have significantly increased the number of quasars with reliable reverberation-map…

astro-ph.HE2024★ 9 cited

Connecting the X-ray/UV variability of Fairall 9 with NICER: A Possible Warm Corona

Ethan R. Partington, Edward M. Cackett, Rick Edelson +7

The Seyfert 1 AGN Fairall 9 was targeted by NICER, Swift, and ground-based observatories for a 1000-day long reverberation mapping campaign. The following analysis of NICER s…

astro-ph.GA2024

AGN STORM 2: X. The origin of the interband continuum delays in Mrk 817

Hagai Netzer, Michael R. Goad, Aaron J. Barth +26

The local (z=0.0315) AGN Mrk 817, was monitored over more than 500 days with space-borne and ground-based instruments as part of a large international campaign AGN STORM 2. Here, w…

astro-ph.GA2024★ 15 cited

Estimating Masses of Supermassive Black Holes in Active Galactic Nuclei from the Halpha Emission Line

E. Dalla Bontà, B. M. Peterson, C. J. Grier +19

The goal of this project is to construct an estimator for the masses of supermassive black holes in active galactic nuclei (AGNs) based on the broad Halpha emission line. We make u…

astro-ph.GA2024

The SDSS-V Black Hole Mapper Reverberation Mapping Project: A Kinematically Variable Broad-Line Region and Consequences for Masses of Luminous Quasars

Logan B. Fries, Jonathan R. Trump, Keith Horne +27

We present a velocity-resolved reverberation mapping analysis of the hypervariable quasar RM160 (SDSS J141041.25+531849.0) at z = 0.359 with 153 spectroscopic epochs of data repres…

astro-ph.HE2024★ 20 cited

AGN STORM 2. VII. A Frequency-resolved Map of the Accretion Disk in Mrk 817: Simultaneous X-ray Reverberation and UVOIR Disk Reprocessing Time Lags

Collin Lewin, Erin Kara, Aaron J. Barth +35

X-ray reverberation mapping is a powerful technique for probing the innermost accretion disk, whereas continuum reverberation mapping in the UV, optical, and infrared (UVOIR) revea…

astro-ph.GA2024

The SDSS-V Black Hole Mapper Reverberation Mapping Project: Multi-Line Dynamical Modeling of a Highly Variable Active Galactic Nucleus with Decade-long Light Curves

Zachary Stone, Yue Shen, Scott F. Anderson +15

We present dynamical modeling of the broad-line region (BLR) for the highly variable AGN SDSS J141041.25+531849.0 () using photometric and spectroscopic monitoring data…

astro-ph.HE2024

Intensive broadband reverberation mapping of Fairall 9 with 1.8 years of daily Swift monitoring

R. Edelson, B. M. Peterson, J. Gelbord +5

We present 1.8 years of near-daily Swift monitoring of the bright, strongly variable Type 1 AGN Fairall 9. Totaling 575 successful visits, this is the largest such campaign reporte…