Title: The X-ray to UV/optical variability of radio-quiet AGNs

Speaker: 蔡振翼

Institute: 中国科学技术大学

Host: 孙谋远

Time: 14:30-16:30, Thursday

Location: Physics Building 552

Abstract:

I will briefly overview the main observational characteristics of AGN variability, including the interband correlations and lags among X-ray/UV/optical continua. These variation properties are usually understood within the widespread X-ray reprocessing scenario, however, several challenges against this scenario have been unveiled. Instead, I will show that in our recent works we demonstrate that the AGN variability is probably attributed to disk turbulences within a fluctuating accretion disk toy model. Finally, further improvement in our scenario as well as the relevant scientific goals of the Wide Field Survey Telescope jointly developed by USTC and PMO will be introduced.

Bio:

Zhen-Yi Cai obtained his BS in physics from Xiamen University (XMU) in 2007, and his PhD in astrophysics in 2013 through a joint PhD project between XMU and SISSA (Italy). From 2014 to 2020, he successively works as a postdoctoral and then an associate researcher in the Department of Astronomy at the University of Science and Technology of China (USTC). Since April 2020, he is an associate professor at USTC. His main research interests include galaxy evolution, variability of active galactic nuclei, and time-domain astronomy. He is going to engage in the data reduction pipeline for the Wide Field Survey Telescope jointly developed by USTC and Purple Mountain Observatory.

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