Friday, March 31, 2017
Rapidly rotating exoplanets, brown dwarfs and massive stars
Kotaro Fujisawa, Waseda University
Stars have rotations, exoplanets have rotations and brown dwarfs have rotations. Some of them display detectable and rapid rotations. For example, Beta Pictoris b is one of the fast spinning exoplanets. The evidence of the planetary rotation has been observed and its rotation velocity is higher than that of Jupiter in the solar system. Some brown dwarfs also have rapid rotations. Their rotation periods are only a few hours and rotation velocities are much higher than those of planets. The shapes of them might be oblate due to the strong centrifugal forces. Therefore, their outer layers cannot be well described by spherical models due to their fast rotations and so non-spherical models are required to describe them. Recently, we have developed a new numerical method for obtaining structures of rapidly rotating objects based on a self-consistent field scheme. In order to consider the structures of the rapidly rotating exoplanets and brown dwarfs, we calculated both thermal evolution and rotating structures of them using MESA code and our new numerical method. I will discuss the evolution of rapidly rotating exoplanets and brown dwarfs. We can also calculate rapidly rotating massive stars and progenitor models for core-collapse supernova using our new numerical method. We have succeeded in obtaining parametric progenitor models with shellular rotation using our numerical method. I will also talk about the rapidly rotating progenitor models.