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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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NGC 2617 brightens again after long very low stateстатья
- Авторы: Oknyansky V.L., Бурлак М.А., Маланчев К.Л., Gaskell C.M., Липунов В.М., Huseynov N.A., Alekberov I.A., Mikailov K.M., Tsygankov S.S., Brotherton M.B., Kasper D., Pu D., Горбовской Е.С., Chen X., BuckleyD A.H., Winkler H., Paul B., van Wyk F., Rebolo R., Serra-Ricart M., Podesta R., Levato H., Шатский Н.И., Татарников А.М., Метлов В.Г.
- Журнал: The Astronomer’s Telegram
- Номер: 11703
- Год издания: 2018
- Аннотация: NGC 2617 is typical example of a changing-look AGN. It has been observed to undergo a dramatic change from a largely obscured Seyfert 1.8 to an unobscured Seyfert 1 from 2003 to 2013 (Shappee et al. 2013, ATel #5010, Shappee et al. 2014). In Jan. 2016 we began spectroscopic and photometric (IR JHK and optical BVRI) monitoring of NGC 2617 to see if it was still in a Seyfert 1 state (for details see Oknaynsky et al. 2016, ATel #9015, #9030, #9050; Oknaynsky et al. 2017, MNRAS, 467, 1496; Oknyansky et al. 2017, arXiv:171102631O). In 2016 and 2017 NGC 2617 brightened again to a level of activity close to that in 2013 April. However, from the beginning of April 2017 till the end of May 2018 the object had very low level of brightness and variability. In December 2017 the X-ray flux was the lowest since monitoring began in 1982 with UVW1 = 15.16 +/- 0.03, B=15.60 +/- 0.03 (Swift). A similar deep minimum was observed in April-May 2018 from the optical data. Our most recent optical spectra obtained in April-May this year showed a very low intensity of the broad H-beta line. Here we report a new recent brightening revealed by MASTER Global Robotic Network data. This is after the very long low state during the previous year. At the start of June 2018 NGC 2617 has brightened again and it now has a B magnitude of about 14.9 +/- 0.05.
- Добавил в систему: Окнянский Виктор Львович