A global look at X‐ray time lags in Seyfert galaxies. Issue 4 (May 2016)

• Record Type: Journal Article
• Authors: Kara, E.; Alston, W.; Fabian, A.
• Is Part Of: Astronomische Nachrichten. Volume 337:Issue 4-5(2016)
• Page Start: 473
• Page End: 478
• Publication Date: 2016-05
• Subjects: accretion, accretion disks -- black hole physics -- galaxies: nuclei -- galaxies: Seyfert -- X‐rays: galaxies; Astronomy -- Periodicals; 520.5
• DOI: 10.1002/asna.201612332
• Languages: English
• ISSNs: 0004-6337

Abstract

Abstract: 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 bare Seyfert galaxies. In this work, we expand the study of X‐ray time lags to all Seyfert galaxies in the XMM‐ Newton archive above a nominal rms and exposure level. We find that reverberation is found in >50 % of sources (with >99 % confidence). We also find that the low‐frequency hard lag (which is likely associated with the coronal emission) is found in >80% of sources, suggesting that most sources with X‐ray variability show intrinsic variability from the nuclear region. We update the known iron K lag amplitude vs. black hole mass relation. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)