Studies of Seyfert galaxies in Fesenkov Astrophysical Institute

Abstract

This article provides an overview of the main research results of a large group of Seyfert galaxies, carried out at Fesenkov Astrophysical Institute (FAI) over the past 50 years. Spectral observations have been performed since 1970. At an early stage, a three cascade image-tube (UM-92) was used as a radiation receiver. In the 1990s, the equipment was modernized, and at present, the modern CCD cameras are used as radiation detectors at the output of spectrographs. The results of observations were used to determine the absolute fluxes of the emission lines and to study their profiles. Several additional emission features were detected on the wings of the broad emission lines Hα in the spectra of two galaxies NGC 4151 and Ark 120. These features are emitted by compact ionized objects, rotating in the field of Central Body (CB). Photometric observations of Seyfert galaxies have been carried out at FAI since 2010. Light curves of more than 20 Seyfert galaxies have been obtained. In particular, the light curves of the galaxy NGC 4151, obtained last years, shows that an active stage of its nucleus took place in 2015-2016, when the brightness increased by 0m.5 in the V filter, and by almost 2m in the R filter. Then, in 2018-2019 there was a rather sharp decline of brightness, and B V R magnitudes returned to their minimal values.