500 citations · 9.7k across the 184 of their papers we have counts for
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The Birth of a Relativistic Jet Following the Disruption of a Star by a Cosmological Black Hole
Dheeraj R. Pasham, Matteo Lucchini, Tanmoy Laskar +63
A black hole can launch a powerful relativistic jet after it tidally disrupts a star. If this jet fortuitously aligns with our line of sight, the overall brightness is Doppler boos…
Explaining the moderate UV/X-ray correlation in AGN
Christos Panagiotou, Erin Kara, Michal Dovčiak
The UV/optical and X-ray variability of active galactic nuclei (AGN) have long been expected to be well correlated as a result of the X-ray illumination of the accretion disk. Rece…
TPHO: a time-dependent photoionisation model for AGN outflows
Daniele Rogantini, Missagh Mehdipour, Jelle Kaastra +3
Outflows in active galactic nuclei (AGN) are considered a promising candidate for driving AGN feedback at large scales. However, without information on the density of these outflow…
X-ray Reverberation Mapping of Ark 564 using Gaussian Process Regression
Collin D. Lewin, Erin Kara, Daniel R. Wilkins +15
Ark 564 is an extreme high-Eddington Narrow-line Seyfert 1 galaxy, known for being one of the brightest, most rapidly variable soft X-ray AGN, and for having one of the lowest temp…
A dense star in a 51-minute orbital period eclipsing binary
Kevin B. Burdge, Kareem El-Badry, Thomas R. Marsh +24
In over a thousand known cataclysmic variables (CVs), where a white dwarf is accreting from a hydrogen-rich star, only a dozen have orbital periods below 75 minutes. One way to ach…
The long stare at Hercules X-1 -- I. Emission lines from the outer disk, the magnetosphere boundary and the accretion curtain
P. Kosec, E. Kara, A. C. Fabian +11
Hercules X-1 is a nearly edge-on accreting X-ray pulsar with a warped accretion disk, precessing with a period of about 35 days. The disk precession allows for unique and changing…
The Host Galaxy and Rapidly Evolving Broad-line Region in the Changing-look Active Galactic Nucleus 1ES 1927+654
Ruancun Li, Luis C. Ho, Claudio Ricci +4
Changing-look active galactic nuclei (AGNs) present an important laboratory to understand the origin and physical properties of the broad-line region (BLR). We investigate follow-u…
A physical model for the UV/optical power spectra of AGN
Christos Panagiotou, Iossif Papadakis, Erin Kara +2
The UV/optical variability of AGN has long been thought to be driven by the X-ray illumination of the accretion disk. However, recent multi-wavelength campaigns of nearby Seyfert g…
Evolution of a Relativistic Outflow and X-ray Corona in the Extreme Changing-Look AGN 1ES 1927+654
Megan Masterson, Erin Kara, Claudio Ricci +8
1ES 1927+654 is a paradigm-defying AGN and one of the most peculiar X-ray nuclear transients. In early 2018, this well-known AGN underwent a changing-look event, in which broad opt…
Black holes: Timing and spectral properties and evolution
Emrah Kalemci, Erin Kara, John A. Tomsick
We review the timing and spectral evolution of black hole X-ray binary systems, with emphasis on the current accretion-ejection paradigm. When in outburst, stellar mass black hole…
SRGA J181414.6-225604: A new Galactic symbiotic X-ray binary outburst triggered by an intense mass loss episode of a heavily obscured Mira variable
Kishalay De, Ilya Mereminskiy, Roberto Soria +24
We present the discovery and multi-wavelength characterization of SRGA J181414.6-225604, a Galactic hard X-ray transient discovered during the ongoing SRG/ART-XC sky survey. Using…
A 62-minute orbital period black widow binary in a wide hierarchical triple
Kevin B. Burdge, Thomas R. Marsh, Jim Fuller +30
Over a dozen millisecond pulsars are ablating low-mass companions in close binary systems. In the original "black widow", the 8-hour orbital period eclipsing pulsar PSR J1959+2048…
The NICER "Reverberation Machine": A Systematic Study of Time Lags in Black Hole X-Ray Binaries
Jingyi Wang, Erin Kara, Matteo Lucchini +12
We perform the first systematic search of all NICER archival observations of black hole (and candidate) low-mass X-ray binaries for signatures of reverberation. Reverberation lags…
Ejection-accretion connection in NLS1 AGN 1H 1934-063
Yerong Xu, Ciro Pinto, Erin Kara +7
Accretion and ejection of matter in active galactic nuclei (AGN) are tightly connected phenomena and represent fundamental mechanisms regulating the growth of the central supermass…
The complex time and energy evolution of quasi-periodic eruptions in eRO-QPE1
R. Arcodia, G. Miniutti, G. Ponti +8
Quasi-periodic eruptions (QPEs) are recurrent X-ray bursts found so far in the nuclei of low-mass galaxies. Their trigger mechanism is still unknown, but recent models involving on…