OGLE16aaa - a Signature of a Hungry Super Massive Black Hole

Łukasz Wyrzykowski; M. Zieliński; Z. Kostrzewa-Rutkowska; A. Hamanowicz; P. G. Jonker; I. Arcavi; J. Guillochon; P. J. Brown; S. Kozłowski; A. Udalski; M. K. Szymański; I. Soszyński; R. Poleski; P. Pietrukowicz; J. Skowron; P. Mróz; K. Ulaczyk; M. Pawlak; K. A. Rybicki; J. Greiner; T. Krühler; J. Bolmer; S. J. Smartt; K. Maguire; K. Smith

doi:10.1093/mnrasl/slw213

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arXiv · 1606.03125

OGLE16aaa - a Signature of a Hungry Super Massive Black Hole

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Abstract

We present the discovery and first three months of follow-up observations of a currently on-going unusual transient detected by the OGLE-IV survey, located in the centre of a galaxy at redshift z=0.1655. The long rise to absolute magnitude of -20.5 mag, slow decline, very broad He and H spectral features make OGLE16aaa similar to other optical/UV Tidal Disruption Events (TDEs). Weak narrow emission lines in the spectrum and archival photometric observations suggest the host galaxy is a weak-line Active Galactic Nucleus (AGN), which has been accreting at higher rate in the past. OGLE16aaa, along with SDSS J0748, seems to form a sub-class of TDEs by weakly or recently active super-massive black holes (SMBHs). This class might bridge the TDEs by quiescent SMBHs and flares observed as "changing-look QSOs", if we interpret the latter as TDEs. If this picture is true, the previously applied requirement for identifying a flare as a TDE that it had to come from an inactive nucleus, could be leading to observational bias in TDE selection, thus affecting TDE-rate estimations.

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Łukasz Wyrzykowski, M. Zieliński, Z. Kostrzewa-Rutkowska, A. Hamanowicz, P. G. Jonker, I. Arcavi, J. Guillochon, P. J. Brown, S. Kozłowski, A. Udalski, M. K. Szymański, I. Soszyński, R. Poleski, P. Pietrukowicz, J. Skowron, P. Mróz, K. Ulaczyk, M. Pawlak, K. A. Rybicki, J. Greiner, T. Krühler, J. Bolmer, S. J. Smartt, K. Maguire, K. Smith. 2016-06-09. OGLE16aaa - a Signature of a Hungry Super Massive Black Hole. https://doi.org/10.1093/mnrasl%2Fslw213

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