Journal
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 501, Issue 1, Pages 483-490Publisher
OXFORD UNIV PRESS
DOI: 10.1093/mnras/staa3636
Keywords
binaries: close; stars: evolution; stars: individual: HD 201433; stars: oscillations; stars: rotation; stars: variables: general
Categories
Funding
- Rose Hills Foundation
- Sloan Foundation [FG-2018-10515]
Ask authors/readers for more resources
In close binary star systems, self-excited pulsating stars can experience an 'inverse' tidal process where tidal interactions with unstable pulsation modes transfer energy in the opposite direction, causing the stellar spins to move away from synchronicity and potentially increasing eccentricity and spin-orbit misalignment. This phenomenon is most likely to occur in main-sequence gravity mode pulsators with orbital periods of a few days.
In close binary stars, the tidal excitation of pulsations typically dissipates energy, causing the system to evolve towards a circular orbit with aligned and synchronized stellar spins. However, for stars with self-excited pulsations, we demonstrate that tidal interaction with unstable pulsation modes can transfer energy in the opposite direction, forcing the spins of the stars away from synchronicity, and potentially pumping the eccentricity and spin-orbit misalignment angle. This 'inverse' tidal process only occurs when the tidally forced mode amplitude is comparable to the mode's saturation amplitude, and it is thus most likely to occur in main-sequence gravity mode pulsators with orbital periods of a few days. We examine the long-term evolution of inverse tidal action, finding the stellar rotation rate can potentially be driven to a very large or very small value, while maintaining a large spin-orbit misalignment angle. Several recent asteroseismic analyses of pulsating stars in close binaries have revealed extremely slow core rotation periods, which we attribute to the action of inverse tides.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available