2016/05/09 by E. Kara, Erin Kara, W. N. Alston +8 · 249 citations
Physics and Astronomy · #Accretion (finance) #Active galactic nucleus #Advanced X-ray Imaging Techniques #Amplitude #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Black hole (networking) #Galaxy #Light curve #Physics #Pulsars and Gravitational Waves Research #Reverberation #Reverberation mapping #Supermassive black hole #astro-ph.HE
paper · pdf · doi:10.1093/mnras/stw1695
published in Monthly Notices of the Royal Astronomical Society 462(1), 511-531 (Oxford University Press) · 22 pages, 9 figures, accepted for publication in MNRAS
arxiv created 2016/05/09 · openalex publication_date 2016/07/15 · arxiv updated 2016/10/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
X-ray reverberation, where light-travel time delays map out the compact geometry around the inner accretion flow in supermassive black holes, has been discovered in several of the brightest, most variable and well-known Seyfert galaxies. In this work, we expand the study of X-ray reverberation to all Seyfert galaxies in the XMM–Newton archive above a nominal rms variability and exposure level (a total of 43 sources). Approximately 50 per cent of sources exhibit iron K reverberation, in that the broad iron K emission line responds to rapid variability in the continuum. We also find that on long time-scales, the hard band emission lags behind the soft band emission in 85 per cent of sources. This ‘low-frequency hard lag’ is likely associated with the coronal emission, and so this result suggests that most sources with X-ray variability show intrinsic variability from the nuclear region. We update the known iron K lag amplitude versus black hole mass relation, and find evidence that the height or extent of the coronal source (as inferred by the reverberation time delay) increases with mass accretion rate.