Quasi Periodic Oscillations in Supermassive Black Holes using TESS.

Quasi-periodic Oscillations (QPOs) have been observed in supermassive black holes across the whole electromagnetic spectrum. The claimed timescales range from a few tens of minutes to days, to weeks, and even years. Different models have been proposed to explain these QPOs which are primarily based on the timescales of periodicity. The rapid, uninterrupted cadence of the space-based TESS exoplanet satellite has opened a new short-timescale parameter space to QPO searches. I will report on the discovery of four QPOs in the TESS light curves of blazars generated by QUAVER which is a customized pipeline to obtain TESS light curves for AGNs. I will discuss the kink instability model employed to explain the timescales of the order of a few days obtained using this instrument. I will also discuss the practical problems encountered in the analysis of these light curves (irregularity, gaps, stationarity, etc.).