ИСТИНА

NGC 2617 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. 2014). We present recent spectroscopic and photometric (NIR and optical) monitoring of NGC 2617. We find that it remains in high state still and can still be classified as a Seyfert1. However, the optical and NIR continuum and Balmer-line luminosity have decreased significantly relative to the maximum Shappee et al. observed in 2013. We also present an optical light curve for 2009 – 2016 from the MASTER Global Robotic Network. This suggests that the dramatic change in Seyfert type of NGC2617 was not connected with brightening observed at 2013 but probably happened between October 2010 and February 2012. From reanalysis of the Shappee et al. (2014) data we find that the K band lags the U band by about 11 days while the J and H bands lag the U band by 3 – 4 days. Unlike Shappee et al., we interpret the K-band emission as being due to re-radiation by dust while the J and H-band emission is due to a combination of radiation from the accretion disk and re-radiation by the hot dust. We consider a model where dust is located in a hollow bi-conical outflow of which we only see the near side. In this model the 11-day lag for the NIR can correspond to emission more than 11 light days from the central source. We propose that the large outburst of NGC 2617 sublimated dust in the outflow to give a clearer view of the broad-line region. If the outburst was due to tidal disruption of a star we predict that the dust will be recreated and NGC 2617 will revert to being a Seyfert 1.8.