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arXiv · 1805.12154

Evidence for an Optical Low-frequency Quasi-Periodic Oscillation in the Kepler Light Curve of an Active Galaxy

Krista Lynne Smith·Richard F. Mushotzky·Patricia T. Boyd·Robert V. Wagoner
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Abstract

We report evidence for a quasi-periodic oscillation (QPO) in the optical light curve of KIC 9650712, a narrow-line Seyfert 1 galaxy in the original Kepler field. After the development and application of a pipeline for Kepler data specific to active galactic nuclei (AGN), one of our sample of 21 AGN selected by infrared photometry and X-ray flux demonstrates a peak in the power spectrum at log $\nu$ = -6.58 Hz, corresponding to a temporal period of t=44 days. We note that although the power spectrum is well-fit by a model consisting of a Lorentzian and a single power law, alternative continuum models cannot be ruled out. From optical spectroscopy, we measure the black hole mass of this AGN as log $M_{\mathrm{BH}} / M_\odot$ = 8.17. We find that this frequency lies along a correlation between low-frequency QPOs and black hole mass from stellar and intermediate mass black holes to AGN, similar to the known correlation in high-frequency QPOs.

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Krista Lynne Smith, Richard F. Mushotzky, Patricia T. Boyd, Robert V. Wagoner. 2018-05-30. Evidence for an Optical Low-frequency Quasi-Periodic Oscillation in the Kepler Light Curve of an Active Galaxy. https://doi.org/10.3847/2041-8213%2Faac88c

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