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

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 نشر من قبل Ranieri Diego Baldi
 تاريخ النشر 2015
  مجال البحث فيزياء
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 تأليف Ranieri D. Baldi




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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 ($pm3sigma$ 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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