SHAO Astrophysics Colloquium

Title: Magnetized Stars from Normal to Supermassive Ones

Time: 3:00pm, Sep. 30th (Thursday)

Speaker:  YU-QING LOU  楼宇庆

Institution: Tsinghua University, Physics Department, Tsinghua Center for Astrophysics, Astronomy Department, and Tsinghua--National Astronomical Observatories of China joint Research Center for Astrophysics

Abstract:

In the framework of general relativity (GR), we investigate magnetized normal to supermassive stars in quasi spherical equilibrium and radial pulsational GR magnetohydrodynamic (MHD) stability/instability problems. In our stellar model, a random transverse magnetic field is presumed and a key relation for magnetic flux conservation is stipulated. We identify distinct features and pertinent physical effects for magnetized and non-magnetic stars. In particular, GR MHD collapses of magnetized massive stars can give rise to black holes (BHs) in a very broad mass range and can certainly avoid the electron-positron pair instabilities to form BHs in the so-called "forbbiden zone of BH masses". This closely relates to the recent inferences of LIGO/Virgo experiments on binary BH masses. We briefly discuss the dynamic or MHD formation of supermassive BHs and hypermassive BHs.