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X-ray/UVOIR Frequency-resolved Time Lag Analysis of Mrk 335 Reveals Accretion Disk Reprocessing
Collin Lewin, Erin Kara, Edward M. Cackett +4
UV and optical continuum reverberation mapping is powerful for probing the accretion disk and inner broad-line region. However, recent reverberation mapping campaigns in the X-ray,…
UV/Optical disk reverberation lags despite a faint X-ray corona in the AGN Mrk 335
Erin Kara, Aaron J. Barth, Edward M. Cackett +37
We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an un…
The multi-epoch X-ray tale of I Zwicky 1 outflows
Daniele Rogantini, Elisa Costantini, Luigi Gallo +3
The narrow-line Seyfert 1 galaxy I Zwicky 1 shows a unique and complex system of ionised gas in outflow, which consists of an ultra-fast wind and a two-component warm absorber. In…
A deep, multi-epoch Chandra HETG study of the ionized outflow from NGC 4051
A. Ogorzalek, A. L. King, S. W. Allen +2
Actively accreting supermassive black holes significantly impact the evolution of their host galaxies, truncating further star formation by expelling large fractions of gas with wi…
High-density disc reflection spectroscopy of low-mass active galactic nuclei
L. Mallick, A. C. Fabian, J. A. García +13
The standard alpha-disc model predicts an anti-correlation between the density of the inner accretion disc and the black hole mass times square of the accretion rate, as seen in hi…
Acceleration and cooling of the corona during X-ray flares from the Seyfert galaxy I Zw 1
D. R. Wilkins, L. C. Gallo, E. Costantini +2
We report on X-ray flares that were observed from the active galactic nucleus I Zwicky 1 (I Zw 1) in 2020 January by the NuSTAR and XMM-Newton observatories. The X-ray spectrum is…
Light bending and X-ray echoes from behind a supermassive black hole
D. R. Wilkins, L. C. Gallo, E. Costantini +2
The innermost regions of accretion disks around black holes are strongly irradiated by X-rays that are emitted from a highly variable, compact corona, in the immediate vicinity of…
Modelling the Multiwavelength Variability of Mrk 335 using Gaussian Processes
Ryan-Rhys Griffiths, Jiachen Jiang, Douglas J. K. Buisson +12
The optical and UV variability of the majority of AGN may be related to the reprocessing of rapidly-changing X-ray emission from a more compact region near the central black hole.…
Lifting the curtain: The Seyfert galaxy Mrk 335 emerges from deep low-state in a sequence of rapid flare events
S. Komossa, D. Grupe, L. C. Gallo +7
The narrow-line Seyfert 1 galaxy Mrk 335 was one of the X-ray brightest AGN, but it has systematically faded since 2007. Here, we report the discovery with Swift of a sequence of b…
Characterising continuum variability in the radio-loud narrow-line Seyfert 1 galaxy IRAS 17020+4544
A. G. Gonzalez, L. C. Gallo, P. Kosec +4
We present results of temporal and spectral analyses on four XMM-Newton EPIC pn observations of IRAS 17020+4544, a narrow-line Seyfert 1 galaxy with evidence of a radio jet. Analys…
Venturing beyond the ISCO: Detecting X-ray emission from the plunging regions around black holes
D. R. Wilkins, C. S. Reynolds, A. C. Fabian
We explore how X-ray reverberation around black holes may reveal the presence of the innermost stable circular orbit (ISCO), predicted by General Relativity, and probe the dynamics…
The Soft State of the Black Hole Transient Source MAXI J1820+070: Emission from the Edge of the Plunge Region?
A. C. Fabian, D. J Buisson, P. Kosec +18
The Galactic black hole X-ray binary MAXI J1820+070 had a bright outburst in 2018 when it became the second brightest X-ray source in the Sky. It was too bright for X-ray CCD instr…
Blueshifted absorption lines from X-ray reflection in IRAS 13224-3809
A. C. Fabian, C. S. Reynolds, J. Jiang +17
We explore a disc origin for the highly-blueshifted, variable absorption lines seen in the X-ray spectrum of the Narrow Line Seyfert 1 galaxy IRAS13224-3809. The blueshift correspo…
A dynamic black hole corona in an active galaxy through X-ray reverberation mapping
William N. Alston, Andrew C. Fabian, Erin Kara +18
X-ray reverberation echoes are assumed to be produced in the strongly distorted spacetime around accreting supermassive black holes. This signal allows us to spatially map the geom…
Low frequency X-ray timing with Gaussian processes and reverberation in the radio-loud AGN 3C 120
D. R. Wilkins
A framework is developed to perform Fourier-domain timing analysis on X-ray light curves with gaps, employing Gaussian processes to model the probability distribution underlying th…
Characterisation of the Particle-Induced Background of XMM-Newton EPIC-pn: Short and Long Term Variability
Esra Bulbul, Ralph Kraft, Paul Nulsen +16
The particle-induced background of X-ray observatories is produced by Galactic Cosmic Ray (GCR) primary protons, electrons, and He ions. Events due to direct interaction with the d…
Supermassive Black Hole Spin and Reverberation
A. Zoghbi, D. R. Wilkins, L. Brenneman +7
X-ray reverberation mapping has emerged as a powerful probe of microparsec scales around AGN, and with high sensitivity detectors, its full potential in echo-mapping the otherwise…
Black hole magnetosphere with small scale flux tubes--II. Stability and dynamics
Yajie Yuan, Anatoly Spitkovsky, Roger D. Blandford +1
In some Seyfert Galaxies, the hard X-rays that produce fluorescent emission lines are thought to be generated in a hot corona that is compact and located at only a few gravitationa…
Black hole magnetosphere with small scale flux tubes
Yajie Yuan, Roger D. Blandford, Dan R. Wilkins
There is observational evidence that the X-ray continuum source that creates the broad fluorescent emission lines in some Seyfert Galaxies may be compact and located at a few gravi…
Detection of polarized gamma-ray emission from the Crab nebula with Hitomi Soft Gamma-ray Detector
Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +191
We present the results from the Hitomi Soft Gamma-ray Detector (SGD) observation of the Crab nebula. The main part of SGD is a Compton camera, which in addition to being a spectrom…
The 1.5 Ms Observing Campaign on IRAS 13224-3809: X-ray Spectral Analysis I
J. Jiang, M. L. Parker, A. C. Fabian +16
We present a detailed spectral analysis of the recent 1.5\,Ms XMM-Newton observing campaign on the narrow line Seyfert 1 galaxy IRAS~132243809, taken simultaneously with 500\,ks…
Variable blurred reflection in the narrow-line Seyfert 1 galaxy Mrk 493
K. Bonson, L. C. Gallo, D. R. Wilkins +1
We examine a 200 ks XMM-Newton observation of the narrow-line Seyfert 1 galaxy Mrk 493. The active galaxy was half as bright as in a previous 2003 snapshot observation and the curr…
Hitomi X-ray Observation of the Pulsar Wind Nebula G21.50.9
Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +194
We present results from the Hitomi X-ray observation of a young composite-type supernova remnant (SNR) G21.50.9, whose emission is dominated by the pulsar wind nebula (PWN) cont…
Atomic data and spectral modeling constraints from high-resolution X-ray observations of the Perseus cluster with Hitomi
Hitomi Collaboration, Felix Aharonian, Hiroki Akamatsu +192
The Hitomi SXS spectrum of the Perseus cluster, with 5 eV resolution in the 2-9 keV band, offers an unprecedented benchmark of the atomic modeling and database for hot collis…