205 citations · 438 across the 19 of their papers we have counts for
11 papers · 1 filter
Quasi-periodic eruption spectral-timing: EMRIs crossing warped accretion disks
Joheen Chakraborty, Andrew Mummery, Eliot Quataert +3
Quasi-periodic eruptions (QPEs) are repeating X-ray transients from galactic nuclei potentially caused by a stellar-mass orbiter repeatedly colliding with the accretion disk of a s…
Relativistic outflows power a quasi-periodic eruption: constraints on energetics, mass loss, and emission mechanisms
Joheen Chakraborty, Erin Kara, Wenbin Lu +17
Quasi-periodic eruptions (QPEs) are recurring bursts of X-ray radiation originating from supermassive black holes (SMBHs). They are an unprecedented type of structured, high-amplit…
Observations of X-ray quasi-periodic eruptions
Thomas Wevers, Joheen Chakraborty, Erwan Quintin +2
Quasi-periodic eruptions (QPEs) are a novel class of repeating nuclear transients, discovered exclusively in the X-ray band to date. Since their initial discovery in 2019, the QPE…
Rapid Orbital Decay in the Ultracompact Double-degenerate Binary eRASSU J060839.5704014
Rahul Sharma, Chandreyee Maitra, Frank Haberl +9
We present timing and spectral analysis of the recently identified ultracompact double-degenerate (DD) white dwarf binary eRASSU J060839.5704014 using observations from NICER an…
V407 Vul: a triple star system with an AM CVn detectable by gravitational wave observatories
James Munday, Antonio C. Rodriguez, Nicole Reindl +23
The AM CVn class includes mass transferring, ultra-compact double white dwarf binaries with orbital periods on the timescale of minutes. A long-standing puzzle is that none of the…
Stars stably accreting from substellar objects
Aaron Householder, Kaitlyn Shin, Kevin B. Burdge +11
Substellar objects such as brown dwarfs and planets are generally expected to remain detached from their main-sequence host stars unless orbital decay or stellar expansion brings t…
A positive period derivative in the quasi-periodic eruptions of ZTF19acnskyy
Joheen Chakraborty, Saul A. Rappaport, Riccardo Arcodia +9
We report the first direct measurement of the period derivative in a quasi-periodic eruption (QPE), finding a smoothly increasing period with $\dot{P}\approx (1.7\pm 0.02)\times10^…
X-ray Spectral-Timing Properties of Tidal Disruption Events
Joheen Chakraborty, Megan Masterson, Andrew Mummery +4
We perform the first systematic study of the minute-to-hours-timescale stochastic variability observed in the X-ray luminosity of tidal disruption events (TDEs) using XMM-Newton da…
An eclipsing 8.56 minute orbital period mass-transferring binary
Emma T. Chickles, Joheen Chakraborty, Kevin B. Burdge +34
We report the discovery of ATLAS J101342.5-451656.8 (hereafter ATLAS J1013-4516), an 8.56 minute orbital period mass transferring AM Canum Venaticorum binary with mean Gaia magnitu…
Disk-to-Corona State Transition and Extreme X-ray Variability in the Tidal Disruption Event AT2019teq
Vera Berger, Erin Kara, Joheen Chakraborty +2
We present a five-year X-ray spectral and timing analysis of the optically selected Tidal Disruption Event (TDE) AT2019teq, which displays extreme variability, including order-of-m…
XRISM finds the Changing-Look AGN NGC 1365 in an extended low state: A dense, highly ionized outflow obscures the central source
Fatima Zaidouni, Erin Kara, Peter Kosec +21
We present the first XRISM/Resolve observations of the active galactic nucleus, NGC 1365, obtained in 2024 February and July. NGC 1365 is known for rapid transitions between Compto…