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تسجيل مستخدم جديدOn the two main classes of Active Galactic Nuclei
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Paolo Padovani
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Active Galactic Nuclei (AGN) are traditionally divided empirically into two main classes: radio-loud and radio-quiet sources. These labels, which are more than fifty years old, are obsolete, misleading, and wrong. I argue that AGN should be classified based on a fundamentally physical rather than just an observational difference, namely the presence (or lack) of strong relativistic jets, and that we should use the terms jetted and non-jetted AGN instead.
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