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TeV Gamma-Ray Astronomy, Extragalactic Sources
1995With the detection of Markarian 421 at TeV energies, it is clear that AGN’s are serious candidates for study with ground-based TeV telescopes. The explanation of the TeV emission is a major constraint on source models. The exact point of the cut-off in the observed spectrum has implications for cosmology.
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Observational paradoxes in extragalactic astronomy.
Science (New York, N.Y.), 2010According to the present astronomical picture of the universe, all the galaxies condensed out of a diffuse medium about 1010 years ago. This picture arises out of the general belief that we live in an expanding universe. Extrapolating backward in time, it is inferred that the galaxies were all compressed at a beginning epoch into some sort of hot ...
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Extragalactic Radio Sources and X-Ray Astronomy
1981I have been asked to survey a number of aspects of extragalactic radio sources in which the radio and X-ray observations come together to provide complementary information about physical conditions in active systems. Some of these aspects are already well known, for example the X-ray emission of clusters of galaxies and of Type I Seyfert galaxies, but ...
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Astrophotonics: astronomy and modern optics
Astronomy and Astrophysics Review, 2021Robert J Harris
exaly
Imaging Fabry-Perot Interferometry in Extragalactic Astronomy
1989This paper reviews the impact that imaging Fabry-Perot interferometry has made on studies of the velocity fields in external galaxies over the past 20 years. A bibliography of all published papers is given, and some of the main scientific results are summarized. The future role of Fabry-Perot interferometry in extragalactic studies is briefly assessed.
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Astropy: A community Python package for astronomy
Astronomy and Astrophysics, 2013Thomas P Robitaille +2 more
exaly