Luigi Foschini
Published 2017-05-29Version 1
After the discovery of powerful relativistic jets from Narrow-Line Seyfert 1 Galaxies, and the understanding of their similarity with those of blazars, a problem of terminology was born. The word blazar is today associated to BL Lac Objects and Flat-Spectrum Radio Quasars, which are somehow different from Narrow-Line Seyfert 1 Galaxies. Using the same word for all the three classes of AGN could drive either toward some misunderstanding, or to the oversight of some important characteristics. I review the main characteristics of these sources, and finally I propose a new scheme of classification.
Comments: 21 pages, 4 figures. Proceedings of the Conference "Quasars at All Cosmic Epochs" (Padova, Italy, April 2-7, 2017). Submitted to Frontiers in Astronomy and Space Science (Special Issue)
An XMM-Newton Study of Six Narrow-Line Seyfert 1 Galaxies at z = 0.35--0.92
A Radio Detection Survey of Narrow-Line Seyfert 1 Galaxies using Very-Long-Baseline Interferometry at 22 GHz
Do BL Lac Objects and FR I radiogalaxies inhabit the same galaxy environment?
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