Results 71 to 80 of about 288,656 (295)
Review on Active-Galactic Nuclei at hard X-ray energies [PDF]
Proceedings of An INTEGRAL view of the high-energy sky (the first 10 years) - 9th INTEGRAL Workshop and celebration of the 10th anniversary of the launch — PoS(INTEGRAL 2012), 2013 Hard X-ray surveys are an important tool for the study of active galactic nuclei (AGN): they provide almost an unbiased view of absorption in the extragalactic population, allow the study of spectral features such as reflection and high energy cut-off which would otherwise be unexplored and favour the discovery of some blazars at high redshift.
R. Landi +8 more
openaire +2 more sources
An X-ray spectral study of 24 type 1 active galactic nuclei [PDF]
, 1996 I present a study of the X-ray spectral properties of a sample containing 24 type-1 active galactic nuclei using the medium spectral resolution of ``ASCA''. The sample consists of 20 radio-quiet objects and 4 radio-loud objects.
C. Reynolds
semanticscholar +1 more source
A Simple Method for Predicting N H Variability in Active Galactic Nuclei
The Astrophysical Journal, 2023 The unified model of active galactic nuclei (AGNs) includes a geometrically thick obscuring medium to explain the differences between type I and type II AGNs as an effect of inclination angle.
Isaiah S. Cox +6 more
doaj +1 more source
X-rays from active galactic nuclei
The Astrophysical Journal, 1981 Through detailed numerical calculations, we have shown that production of thermal photons at the self-absorbed cyclotron higher harmonics and Comptonization of those soft photons in a hot plasma with the electron temperature 10/sup 9/ K provide a natural mechanism to account for the dominant observed features of the X-ray emission in the active ...
Sachiko Tsuruta +2 more
openaire +2 more sources
The Hard X‐Ray Spectrum as a Probe for Black Hole Growth in Radio‐Quiet Active Galactic Nuclei [PDF]
, 2008 We study the hard X-ray spectral properties of 10 highly luminous radio-quiet (RQ) active galactic nuclei (AGNs) at z = 1.3–3.2, including new XMM-Newton observations of four of these sources.
Ohad Shemmer +4 more
openalex +3 more sources
The X-Ray Polarization of the Accretion Disk Coronae of Active Galactic Nuclei [PDF]
, 2017 Hard X-rays observed in Active Galactic Nuclei (AGNs) are thought to originate from the Comptonization of the optical/UV accretion disk photons in a hot corona.
B. Beheshtipour +2 more
semanticscholar +1 more source
X-RAY DETECTED ACTIVE GALACTIC NUCLEI IN DWARF GALAXIES AT 0 < z < 1 [PDF]
, 2016 We present a sample of accreting supermassive black holes (SMBHs) in dwarf galaxies at . We identify dwarf galaxies in the NEWFIRM Medium Band Survey with stellar masses of that have spectroscopic redshifts from the DEEP2 survey and lie within the region
Kris Pardo +8 more
semanticscholar +1 more source
X-ray variability time scales in active galactic nuclei [PDF]
Astronomy & Astrophysics, 2009 6 pages, 1 figure, accepted for publication in Astronomy and ...
W. Ishibashi, T. J. L. Courvoisier
openaire +3 more sources
X-ray Properties of Radio-Selected Dual Active Galactic Nuclei [PDF]
, 2019 Merger simulations predict that tidally induced gas inflows can trigger kpc-scale dual active galactic nuclei (dAGN) in heavily obscured environments. Previously with the Very Large Array, we have confirmed four dAGN with redshifts between $0.04 < z < 0 ...
Djorgovski, S . G. +4 more
core +2 more sources
A Comparison of the X-Ray Emission from Tidal Disruption Events with those of Active Galactic Nuclei [PDF]
, 2017 One of the main challenges of current tidal disruption events (TDEs) studies is that emission arising from active galactic nucleus (AGN) activity may potentially mimic the expected X-ray emission of a TDE. Here we compare the X-ray properties of TDEs and
K. Auchettl +2 more
semanticscholar +1 more source