Changing looks of the nucleus of Seyfert galaxy NGC 3516 during 2016-2020
Sternberg Astronomical Institute, M. V. Lomonosov Moscow State University（莫斯科国立大学列别杰夫天文研究所）；Shamakhy Astrophysical Observatory, National Academy of Sciences（巴库国家科学院沙马基天体物理观测站）
V. L. Oknyansky, Kh. M. Mikailov, N. A. Huseynov
备注：
12 pages, 4 figures, accepted by Astronomy Reports
发表信息：
Astronomy Reports, Vol. 64, No 12, pp. 979-984, 2020
The results of spectral observations of NGC 3516 with the 2-m telescope of the Shamakhy Astrophysical Observatory during 2016-2020 are presented. In the first half of 2016, the intensive broad component Hbeta was found, which indicates a spectral type change compared to 2014, when the broad component was almost invisible. In the second half of 2016, the broad component H$β$ again was weakened and was practically not observed, remaining as weak until the end of 2019. At the end of 2019, the broad component Hbeta strengthened again, and in May 2020 reached a typical level for the high state of the object. During 2016-2020 we observed several changing looks of NGC 3516.
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