Extended Data Fig. 1: Unbinned PSDs from the 2–10 keV light curves with 20s binning for ObsIDs 0915390701, 0931791401, 0932392001, and 0932392101.
From: Millihertz oscillations near the innermost orbit of a supermassive black hole
The resulting MCMC fit to a power-law or Lorentzian broadband noise model is shown in orange or purple, respectively. The shaded regions show a 1σ confidence region. The bottom two panels show the data divided by the power-law and Lorentzian models, highlighting the strong QPO feature at roughly 1.7 mHz (ObsIDs 0915390701), 2.2 mHz (ObsID 0931791401), and 2.3 mHz (ObsIDs 0932392001, 0932392101). These broadband noise models were used to simulate power spectra for estimating the statistical significance of the QPOs.
