^ http://astrothesaurus.org/uat/16

Active galactic nuclei

Instance information

altLabel

AGNs,AGN

broader

http://astrothesaurus.org/uat/609,http://astrothesaurus.org/uat/17,http://astrothesaurus.org/uat/739

contributor

http://editor.vocabs.ands.org.au/user/AAS_Frey.Katie_Admin,http://editor.vocabs.ands.org.au/user/AAS_Frey.Katie

definition

A central region of an active galaxy, which is a light-year or less in diameter and has an abnormally high luminosity. The nucleus emits high energy radiation (gamma rays, X-rays, ultraviolet) and shows variability over various time-scales, sometimes very short (hours to weeks). Emission line spectra reveal high velocity motions up to 10^4 km s^-1. AGNs are divided into two main types. Type I refers to an AGN whose nucleus is visible (the spectra has both narrow and broad emission lines), while in type II AGN, the broad line region (BLR) is obscured and the lines are very narrow. This may be due either to the viewing angle or some intrinsic difference in structure.

modified

2020-11-06T01:47:26.534Z,2020-11-03T17:59:19.234Z

narrower

http://astrothesaurus.org/uat/164,http://astrothesaurus.org/uat/1344,http://astrothesaurus.org/uat/1388,http://astrothesaurus.org/uat/1352,http://astrothesaurus.org/uat/1341,http://astrothesaurus.org/uat/2033,http://astrothesaurus.org/uat/1319,http://astrothesaurus.org/uat/2034,http://astrothesaurus.org/uat/2134,http://astrothesaurus.org/uat/2035,http://astrothesaurus.org/uat/1348,http://astrothesaurus.org/uat/1347

related

http://astrothesaurus.org/uat/2017,http://astrothesaurus.org/uat/1358

Instance relations

Types