IC 3599 did it again: A second outburst of the X-ray transient Seyfert 1.9 Galaxy

摘要: We report on the Swift discovery of a second high-amplitude (factor 100) outburst Seyfert 1.9 galaxy IC 3599, and discuss implications for scenarios. detected this active galactic nucleus (AGN) again in February 2010 X-rays at level (1.50\plm0.11)$\times 10^{36}$ W (0.2-2.0 keV), which is nearly as luminous first with ROSAT 1990. Optical data from Catalina sky survey show that optical emission was already bright two years before X-ray high-state. Our new observations performed between 2013 2015 3599 currently very low flux state. This repeat outburst, long duration, suggest likely not tidal disruption event (TDE). Instead, variants AGN-related variability are explored. The consistent an accretion disk instability around black hole mass order 10$^6$--10$^7$ M$_{\odot}$; value estimated using several different methods.