24 papers
The incidence of eROSITA X-ray AGN in the local Universe: from dwarf to massive galaxies
Z. Igo, A. Merloni, A. Georgakakis +22
Combining deep, wide-area X-ray surveys with multi-wavelength catalogues provides insights into rare, highly-accreting AGN and low-mass galaxies at low redshift, the latter potenti…
Spatially resolved optical and mid-infrared spectroscopy of SDSS1335+0728: implications for the origin of the Ansky event
P. Sánchez-Sáez, M. Masterson, L. Hernández-GarcÃa +25
The galaxy SDSS1335+0728 brightened abruptly in December 2019 (the Ansky event) and has since been confirmed as the host of extreme X-ray quasi-periodic eruptions (QPEs) of debated…
Persistence of the Millihertz X-ray Quasi-Periodic Oscillation in the Active Galactic Nucleus 1ES 1927+654
Megan Masterson, Erin Kara, William N. Alston +15
1ES 1927+654 is an extreme active galactic nucleus (AGN) that has defied our canonical expectations for how AGN appear across the electromagnetic spectrum and how they vary on shor…
Even a precessing clock is right twice per orbit -- The super-periods of eRO-QPE2 and challenges for quasi-periodic eruption orbital models
R. Arcodia, G. Miniutti, J. Chakraborty +25
We present OC (``observed minus calculated'') timing analysis of the quasi-periodic eruption (QPE) source eRO-QPE2 with a multi-mission X-ray campaign, which includes 32 observe…
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…