Results 211 to 220 of about 1,919 (235)

X-ray timing studies of Active Galactic Nuclei

AIP Conference Proceedings, 2008
We present a power spectral analysis survey of 24 active galactic nuclei (AGN). We combine X‐ray observations to produce a power spectrum covering a broad range of Fourier frequencies and fit the power spectrum of each AGN using a single‐bend power‐law model.
D. P. Summons, I. M. McHardy, P. Uttley, P. Arévalo, A. Bhaskar, Ye-Fei Yuan, Xiang-Dong Li, Dong Lai   +7 more
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X-ray observations and the properties of active galactic nuclei

AIP Conference Proceedings, 1990
X‐ray observations and the properties of Active Galactic Nuclei are re ed and the requirements for 21st century observations are discussed. To obtain the data necessary to directly study evolution, determine redshifts, study accretion disks and determine characteristic timescales of variability requires del E about 100 ev, a collecting at E about 6 kev
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X-Ray Timing and Spectral Observations of Active Galactic Nuclei

Space Science Reviews, 1985
Over 500 galaxies with active nuclei (AGN), in which class are included Seyfert galaxies, radio galaxies, QSOs and BL Lacertid-type objects, have so far been detected at X-ray wavelengths. Most of these are faint objects for which the only information available is a flux obtained from an observation with the Einstein Observatory, but somewhere upwards ...
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Optical and X-Ray Properties of Active Galactic Nuclei

1994
The discovery of nuclear activity in galaxies results from the pioneering work of Fathi, Slipher2 and Hubble3. The first found Active Galactic Nuclei (AGN), NGC1068, NGC4051 and NGC4151, displayed not only strong broad permittted emission hydrogen lines (such as Hβ λ4861) but also narrow forbidden ion emission lines, characteristic of well known ...
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The soft X-ray spectra of active galactic nuclei

2008
EXOSAT LE and ME data on Seyfert 1 galaxies and quasars are reviewed: the observations indicate that a strong flux of soft X-rays, in excess of the power-law continuum that extends over most of the spectrum, is a common feature of the emission of Active Galactic Nuclei (AGN).
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Oxygen K-edge X-ray Absorption Spectra

Chemical Reviews, 2020
Federica Frati, Myrtille O J Y Hunault, Frank M F De Groot   +2 more
exaly  

X-ray photoelectron spectroscopy: Towards reliable binding energy referencing

Progress in Materials Science, 2020
Grzegorz Greczynski, Lars Hultman
exaly  

Small Angle X-ray Scattering for Nanoparticle Research

Chemical Reviews, 2016
, Byeongdu Lee
exaly  

Synchrotron X-ray Analytical Techniques for Studying Materials Electrochemistry in Rechargeable Batteries

Chemical Reviews, 2017
Yijin Liu, Xi-Qian Yu, Lei Cheng
exaly  

Simulating X-ray Spectroscopies and Calculating Core-Excited States of Molecules

Chemical Reviews, 2018
Patrick Norman, Andreas Dreuw
exaly