500 citations · 3.6k across the 69 of their papers we have counts for
70 papers
A Disc Reflection Model for Ultra-Soft Narrow-Line Seyfert 1 Galaxies
Jiachen Jiang, Luigi C. Gallo, Andrew C. Fabian +2
We present a detailed analysis of the XMM-Newton observations of five narrow-line Seyfert 1 galaxies (NLS1s). They all show very soft continuum emission in the X-ray band with a ph…
Hunting for the nature of the enigmatic narrow-line Seyfert 1 galaxy PKS 2004-447
M. Berton, G. Peluso, P. Marziani +19
Narrow-line Seyfert 1 (NLS1) galaxies are a class of active galactic nuclei (AGN) that, in some cases, can harbor powerful relativistic jets. One of them, PKS 2004-447, shows gamma…
Light bending and X-ray echoes from behind a supermassive black hole
D. R. Wilkins, L. C. Gallo, E. Costantini +2
The innermost regions of accretion disks around black holes are strongly irradiated by X-rays that are emitted from a highly variable, compact corona, in the immediate vicinity of…
Project MOMO: Multiwavelength Observations and Modelling of OJ 287
S. Komossa, D. Grupe, A. Kraus +9
Our project MOMO (Multiwavelength observations and modelling of OJ 287) consists of dedicated, dense, long-term flux and spectroscopic monitoring and deep follow-up observations of…
The Unusual Weak-Line Quasar PG1407+265 and its Foreground z~0.7 X-ray Cluster
Jonathan C. McDowell, Aneta Siemiginowska, Matthew Ashby +2
We present new observations of the odd weak-line quasar PG1407+265, and report the discovery of CXOU J140927.9+261813, a X-ray cluster. Archival X-ray photometry…
Supermassive binary black holes and the case of OJ 287
S. Komossa, S. Ciprini, L. Dey +12
Supermassive binary black holes (SMBBHs) are laboratories par excellence for relativistic effects, including precession effects in the Kerr metric and the emission of gravitational…