Types of active galaxy

Types of active galaxy - Types of active galaxy It is...

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Types of active galaxy It is convenient to divide AGN into two classes, conventionally called radio-quiet and radio-loud. In the radio-loud objects a contribution from the jet(s) and the lobes they inflate dominates the luminosity of the AGN, at least at radio wavelengths but possibly at some or all others. Radio- quiet objects are simpler since jet and jet-related emission can be neglected. AGN terminology is often confusing, since the distinctions between different types of AGN sometimes reflect historical differences in how objects were discovered or initially classified, rather than real physical differences. Radio-quiet AGN Low-ionization nuclear emission-line regions (LINERs). As the name suggests, these systems show only weak nuclear emission-line regions, and no other signatures of AGN emission. It is debatable whether all such systems are true AGN (powered by accretion on to a supermassive black hole). If they are, they constitute the lowest-luminosity class of radio-quiet AGN. Some may be radio-quiet analogues of the low-excitation radio galaxies
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This note was uploaded on 12/15/2011 for the course AST AST1002 taught by Professor Emilyhoward during the Fall '10 term at Broward College.

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