Multi-Wavelength Observations of Ultra-Luminous X-ray Sources

Abstract: 

Ultra-luminous X-ray sources (ULXs) exhibit super-Eddington luminosities (>10^39 erg/s) under a stellar mass black hole accretion regime, yet the physics and evolution of their super-Eddington accretion remain unclear. Recent observations in optical (including narrow-band imaging, spectroscopy, and IFU) and radio wavelengths have been conducted to unveil not only the nature of the accretion disk but also the extended nebulae associated with ULXs. These nebulae are considered as the result of photo-ionization by ULXs or shock-ionization by the interaction between the interstellar medium (ISM) and the outflow from ULXs. Through multi-wavelength observations of the nebulae, it is possible to estimate the kinetic properties of the outflow and the hydrogen density of the environment, aiding in constraining the super-Eddington accretion model. In this talk, I will provide an overview of current research on ULXs and offer examples illustrating how studies of associated nebulae can inform and constrain accretion models of ULXs.


Speaker: 
Dr. Jing Guo (郭静), Tsinghua University
Place: 
KIAA Shu Qi meeting room
Time: 
Tuesday, May 14, 2024 - 1:30PM to Tuesday, May 14, 2024 - 2:30PM
Biography: 
Dr. Jing Guo completed her bachelor’s degree at Huazhong University of Science and Technology and holds a PhD in astronomy from Xiamen University. Currently a "Shuimu" fellow postdoc at Tsinghua University, her primary research interest lies in revealing the nature of ULXs by investigating their associated "bubbles." She is also a collaborator of the LHAASO group, where she contributes to understanding the acceleration mechanism of cosmic rays through multi-wavelength observations.