500 citations · 9.7k across the 184 of their papers we have counts for
19 papers · 1 filter
Discovery of a soft X-ray lag in the Ultraluminous X-ray Source NGC 1313 X-1
E. Kara, C. Pinto, D. J. Walton +14
Ultraluminous X-ray Sources (ULXs) provide a unique opportunities to probe the geometry and energetics of super-Eddington accretion. The radiative processes involved in super-Eddin…
Relativistic reflection and reverberation in GX 339-4 with NICER and NuSTAR
Jingyi Wang, Erin Kara, James Steiner +8
We analyze seven NICER and NuSTAR epochs of the black hole X-ray binary GX 339-4 in the hard state during its two most recent hard-only outbursts in 2017 and 2019. These observatio…
The nuclear environment of the NLS1 Mrk 335: obscuration of the X-ray line emission by a variable outflow
M. L. Parker, A. L. Longinotti, N. Schartel +12
We present XMM-Newton, NuSTAR, Swift and Hubble Space Telescope observations of the Narrow-line Seyfert 1 galaxy Mrk 335 in a protracted low state in 2018 and 2019. The X-ray flux…
MAXI J1820+070 with NuSTAR I. An increase in variability frequency but a stable reflection spectrum: coronal properties and implications for the inner disc in black hole binaries
D. J. K. Buisson, A. C. Fabian, D. Barret +10
MAXI J1820+070 (optical counterpart ASASSN-18ey) is a black hole candidate discovered through its recent very bright outburst. The low extinction column and long duration at high f…
Discovery and Identification of MAXI J1621-501 as a Type I X-ray Burster with a Super-Orbital Period
Nicholas M. Gorgone, Chryssa Kouveliotou, Hitoshi Negoro +26
MAXI J1621-501 is the first Swift/XRT Deep Galactic Plane Survey transient that was followed up with a multitude of space missions (NuSTAR, Swift, Chandra, NICER, INTEGRAL, and MAX…
High Density Reflection Spectroscopy: II. the Density of the Inner Black Hole Accretion Disc in AGN
Jiachen Jiang, Andrew C. Fabian, Thomas Dauser +7
We present a high density disc reflection spectral analysis of a sample of 17 Seyfert 1 galaxies to study the inner disc densities at different black hole mass scales and accretion…
The high energy universe at ultra-high resolution: the power and promise of X-ray interferometry
Phil Uttley, Roland den Hartog, Cosimo Bambi +24
We propose the development of X-ray interferometry (XRI), to reveal the universe at high energies with ultra-high spatial resolution. With baselines which can be accommodated on a…
Astro2020 APC White Paper: The Early Career Perspective on the Coming Decade, Astrophysics Career Paths, and the Decadal Survey Process
Emily Moravec, Ian Czekala, Kate Follette +53
In response to the need for the Astro2020 Decadal Survey to explicitly engage early career astronomers, the National Academies of Sciences, Engineering, and Medicine hosted the Ear…
X-ray fluorescence from super-Eddington accreting black holes
Lars Lund Thomsen, Jane Lixin Dai, Enrico Ramirez-Ruiz +2
X-ray reverberation has proven to be a powerful tool capable of probing the innermost region of accretion disks around compact objects. Current theoretical effort generally assumes…
A New Class of Changing-Look LINERs
Sara Frederick, Suvi Gezari, Matthew J. Graham +28
We report the discovery of six active galactic nuclei (AGN) caught "turning on" during the first nine months of the Zwicky Transient Facility (ZTF) survey. The host galaxies were c…
Multi-Messenger Astrophysics with Pulsar Timing Arrays
Luke Zoltan Kelley, Maria Charisi, Sarah Burke-Spolaor +29
Pulsar timing arrays (PTAs) are on the verge of detecting low-frequency gravitational waves (GWs) from supermassive black hole binaries (SMBHBs). With continued observations of a l…
Probing the Black Hole Engine with Measurements of the Relativistic X-ray Reflection Component
Javier A. García, Matteo Bachetti, David R. Ballantyne +21
Over the last decades X-ray spectroscopy has proven to be a powerful tool for the estimation of black hole spin and several other key parameters in dozens of AGN and black hole X-r…
Breaking the limit: Super-Eddington accretion onto black holes and neutron stars
M. Brightman, M. Bachetti, H. P. Earnshaw +10
With the recent discoveries of massive and highly luminous quasars at high redshifts (; e.g. Mortlock et al. 2011), the question of how black holes (BHs) grow in the early…
The Advanced X-ray Imaging Satellite
Richard F. Mushotzky, James Aird, Amy J. Barger +41
Much of the baryonic matter in the Universe, including the most active and luminous sources, are best studied in the X-ray band. Key advances in X-ray optics and detectors have pav…
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…
X-ray follow-up of extragalactic transients
Erin Kara, Raffaella Margutti, Azadeh Keivani +11
Most violent and energetic processes in our universe, including mergers of compact objects, explosions of massive stars and extreme accretion events, produce copious amounts of X-r…
1ES 1927+654: An AGN Caught Changing Look on a Timescale of Months
Benny Trakhtenbrot, Iair Arcavi, Chelsea L. MacLeod +21
We study the sudden optical and ultraviolet (UV) brightening of 1ES 1927+654, which until now was known as a narrow-line active galactic nucleus (AGN). 1ES 1927+654 was part of the…
The corona contracts in a black-hole transient
E. Kara, J. F. Steiner, A. C. Fabian +11
The geometry of the accretion flow around stellar-mass black holes can change on timescales of days to months. When a black hole emerges from quiescence (that is, it "turns on" aft…
A new class of flares from accreting supermassive black holes
Benny Trakhtenbrot, Iair Arcavi, Claudio Ricci +26
Accreting supermassive black holes (SMBHs) can exhibit variable emission across the electromagnetic spectrum and over a broad range of timescales. The variability of active galacti…