Speaker
Dr
Michael Zacharias
(TPIV, Ruhr-Univseristät, Bochum, Germany)
Description
In late 2016 and early 2017, the flat spectrum radio quasar CTA 102 (z=1.032) experienced an extraordinary phase of its existence. Starting in October 2016, over the course of two months the gamma-ray flux rose by a factor 50 and decreased again for 2 months to pre-flare levels. This long-term trend has been superposed by short, bright flares, which made CTA 102 one of the brightest gamma-ray sources in the sky despite its large cosmological distance. Simultaneously to the gamma-ray trend, the optical flux has increased by a factor 100, while the X-rays varied by a factor of 10 compared to pre-event observations. We explain the event by the ablation of a passing gas cloud by the jet. This model fits amazingly well the long-term trend and can also account for the short-term outbursts on top of that.
Primary author
Dr
Michael Zacharias
(TPIV, Ruhr-Univseristät, Bochum, Germany)
Co-authors
Ms
Alicja Wierzcholska
(Jagiellonian University)
Mr
Felix Jankowsky
(Landessternwarte Heidelberg)
Dr
Jean-Philippe Lenain
(LPNHE)
Prof.
Markus Boettcher
(North-West University)
Prof.
Stefan Wagner
(LSW Heidelberg)
