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arXiv · 1509.09230

Millimeter-band variability of the radio-quiet nucleus of NGC7469

Ranieri D. Baldi·Ehud Behar·Ari Laor·Assaf Horesh
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Abstract

We report short-cadence monitoring of a radio-quiet Active Galactic Nuclei (AGN), NGC7469, at 95 GHz (3 mm) over a period of 70 days with the CARMA telescope. The AGN varies significantly ($\pm3\sigma$ from the mean) by a factor of two within 4-5 days. The intrinsic 95 GHz variability amplitude in excess of the measurement noise (10%) and relative to the mean flux is comparable to that in the X-rays, and much higher than at 8.4 GHz. The mm-band variability and its similarity to the X-ray variability adds to the evidence that the mm and X-ray emission have the same physical origin, and are associated with the accretion disk corona.

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Ranieri D. Baldi, Ehud Behar, Ari Laor, Assaf Horesh. 2015-09-30. Millimeter-band variability of the radio-quiet nucleus of NGC7469. https://doi.org/10.1093/mnras/stv2284

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