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X-Ray Variability in Active Galactic Nuclei
1998X-ray variability is a distinguishing property of Active Galactic Nuclei (AGN), and the energetics and time scales of the emission dictate that the X-rays must originate very close to the central engine. In this review I discuss two basic topics from AGN variability research.
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X-Ray Spectra of Active Galactic Nuclei
1980There are a variety of galaxies which are classified as nuclearactive, ranging from those which have nuclei which are merely distinguishable from a stellar component all the way to QSO’s. The subject of this lecture will be only those extreme cases (Seyfert I, BL Lac and quasar) which constitute the most intense compact X-ray sources which are ...
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X-ray timing studies of Active Galactic Nuclei
AIP Conference Proceedings, 2008We 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 +7 more
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X-ray observations and the properties of active galactic nuclei
AIP Conference Proceedings, 1990X‐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, 1985Over 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
1994The 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
2008EXOSAT 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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