R-mode oscillations ubiquitous in stars
Main Author: | Saio, Hiideyuki |
---|---|
Other Authors: | "Ballot, Jérôm, Vauclair, Sylvie, Vauclair, Gérard |
Format: | Proceeding Journal |
Terbitan: |
, 2018
|
Online Access: |
https://zenodo.org/record/1912055 |
Daftar Isi:
- We discuss properties and examples of r-mode (large scale Rossby wave) oscillations in rotating stars. Motions are nearly toroidal but affected weakly by buoyancy. R modes seem to be excited mechanically in most cases, and ubiquitous in various types of rotating stars;e.g., fast rotating $\gamma$ Dor stars, spotted stars, eclipsing binary stars, Be stars, and accreting white dwarfs. In the Fourier spectrum of a star, even (i.e., symmetric to the equator) r modes of azimuthal order $m$ appear as a group of frequencies just below $m$ times the rotation frequency. From this property, a rotation frequency can be determined if r modes are detected. We discuss r modes in KIC~8462852 (Boyajian's star), KIC~9117875 (Am star), KIC~6128830 (HgMn star), and the accreting white dwarf in the dwarf nova GW~Lib.