SHAO Astrophysics Colloquium
Title:Galaxy formation in the context of concordance cosmology: confront theory with observations
Speaker: Qi Guo (National Astronomical Observatories, CAS.)
Time: 3:30 pm, June 07 (Thursday)
Location: Lecture Hall, 3rd floor
Abstract:
It has made great progress in the field of galaxy formation and cosmology in the past 30 years. Here I will highlight recent progresses and challenges in galaxy formation models, by comparing model predictions with observations. In particular, I will also present our recent work to use galaxy formation models to explain the formation of a special population of dwarf galaxies, the ultra-diffuse dwarf galaxies (UDG). The UDGs have luminosity of typical dwarf galaxy but with sizes as large as typical L* galaxies. They are preferentially discovered in high dense region, yet lack of tidal features. A great attention has been drawn on the origin of this population. I will show that the UDGs are genuine dwarf galaxies rather than failed L* galaxies.
Seminar
Title: Understanding the X-ray and Multi-wavelength Spectral Variability of super-Eddington NLS1s
Speaker: Chichuan Jin (NAOC)
Time: 10:45 am, June 8 (Friday)
Location: Middle conference room, 3rd floor
Abstract: The study of multi-wavelength spectral variability can provide global constraints on the accretion flow around SMBH. For several years we have been using observational data from various instruments, especially XMM-Newton, to study the multi-wavelength properties of super-Eddington NLS1s. These studies greatly deepen our understanding about AGN accretion. In this presentation, I will talk about general multi-wavelength (especially X-ray) spectral timing properties of unobscured super-Eddington NLS1s, which can be well understood in a unified accretion flow scenario, which contains a standard outer disc, a puffed-up inner disc with strong disc wind and/or advection, an extended soft X-ray corona region and a compact hard X-ray corona region. By considering the inclination angle effect, such a scenario can explain NLS1s with more complex X-ray properties, without requiring a large spin parameter. These results also highlight the requirements for future multi-wavelength simultaneous spectral-timing monitoring programs in order to make further breakthroughs in the study of AGN accretion.
Group meetings
Black hole Accretion and High-energy Astrophysics /Black Hole Feedback and Cosmic Ray Astrophysics Seminar
Location: 1608
Time: 14:00-16:00, Wednesday, June 6
Speaker: Zhiyuan Yao
The Effect of the AGN Feedback on the Interstellar Medium of Early-Type Galaxies: 2D Hydrodynamical Simulations of the Low-Rotation Case
https://ui.adsabs.harvard.edu//#abs/2017ApJ...835...15C
Speaker: Gleniese McKenzie
Blazar Variability from Turbulence in Jets Launched by Magnetically Arrested Accretion Flows
https://ui.adsabs.harvard.edu/?#abs/2017ApJ...843...81O
Active Galactic Nuclei Feedback and the Origin and Fate of the Hot Gas in Early-type Galaxies
http://adsabs.harvard.edu/abs/2018ApJ...856..115P