Speaker: Prof. Qingjuan Yu (KIAA-PKU)

Title: Toward understanding the origin of hypervelocity stars

Time: 2:00PM, January 8th (Friday)

Location: 3rd floor, middle conf. room

Abstract:

Hypervelocity stars (HVSs), with velocities up to 1000 km/s, were predicted to exist in the Galaxy as a consequence of dynamical interactions of stars with the central supermassive black hole. This prediction has been confirmed with the discovery of the first hypervelocity star in the Galactic halo in 2005. In this talk, I will review the dynamical mechanisms of ejecting hypervelocity stars and recent observations. I will talk about how the spatial distribution of HVSs maps the spatial distribution of the parent population of their progenitors directly; and the anisotropic spatial distribution of the detected HVSs suggests that most of the HVSs are probably originated from the central young stellar disk located within half a parsec from the massive black hole in the Galactic center. In addition, I will also talk about the kinematics of hypervelocity stars and how they can be used as a diagnostic tool to constrain the triaxial shape of the Galactic halo potential.