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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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The X-Ray Spectra of Active Galactic Nuclei
Physica Scripta, 1984Recent observations of the X-ray spectra of active galactic nuclei are reviewed. After an outline of the properties of these sources deduced from observations at other wavelengths, the relevance of X-ray spectra to our understanding of the X-ray emission mechanisms and of the ultimate source of energy is discussed.
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Astrophysical Journal
We present a sample of 341 “little red dots” (LRDs) spanning the redshift range z ∼ 2–11 using data from the CEERS, PRIMER, JADES, UNCOVER, and NGDEEP surveys.
D. Kocevski +56 more
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We present a sample of 341 “little red dots” (LRDs) spanning the redshift range z ∼ 2–11 using data from the CEERS, PRIMER, JADES, UNCOVER, and NGDEEP surveys.
D. Kocevski +56 more
semanticscholar +1 more source
X–rays from active galactic nuclei: relativistically broadened emission lines
Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, 2002The X-ray spectra of many Seyfert 1 galaxies show an iron-K emission line. Some of these lines are broad and skew, reflecting the rapid motion of the accreting gas together with the deep gravitational potential of the central black hole. The observational evidence for broad iron lines is reviewed, from ASCA to recent Chandra and XMM-Newton spectra ...
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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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The X-ray variability of active galactic nuclei
2008Recent results relating to the X-ray variability exhibited by active galactic nuclei are reviewed. EXOSAT observations have established, contrary to earlier indications, that X-ray variability on a timescale of an hour or less is a relatively common feature of such sources.
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Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources
Nature, 2021Zhen Cao, Felix Aharonian, Yiwei Bao
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The Galactic Center massive black hole and nuclear star cluster
Reviews of Modern Physics, 2010Reinhard Genzel, Stefan Gillessen
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A fast radio burst associated with a Galactic magnetar
Nature, 2020Christopher Bochenek +2 more
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