A tidally tilted sectoral dipole pulsation mode in the eclipsing binary TIC 63328020

Maxted, Pierrre

doi:10.1093/mnras/stab336

A tidally tilted sectoral dipole pulsation mode in the eclipsing binary TIC 63328020

Maxted, Pierrre

Authors

Pierre Maxted p.maxted@keele.ac.uk

Abstract

We report the discovery of the third tidally tilted pulsator, TIC 63328020. Observations with the TESS satellite reveal binary eclipses with an orbital period of 1.1057 d, and d Scuti-type pulsations with a mode frequency of 21.09533 d-1. This pulsation exhibits a septuplet of orbital sidelobes as well as a harmonic quintuplet. Using the oblique pulsator model, the primary oscillation is identified as a sectoral dipole mode with l = 1, |m| = 1. We find the pulsating star to have M1 ? 2.5?M?, R1 ? 3?R?, and Teff, 1 ? 8000 K, while the secondary has M2 ? 1.1?M?, R2 ? 2?R?, and Teff, 2 ? 5600 K. Both stars appear to be close to filling their respective Roche lobes. The properties of this binary as well as the tidally tilted pulsations differ from the previous two tidally tilted pulsators, HD74423 and CO Cam, in important ways. We also study the prior history of this system with binary evolution models and conclude that extensive mass transfer has occurred from the current secondary to the primary.

Journal Article Type	Article
Acceptance Date	Jan 27, 2021
Publication Date	May 1, 2021
Publicly Available Date	May 30, 2023
Journal	Monthly Notices of the Royal Astronomical Society
Print ISSN	0035-8711
Publisher	Oxford University Press
Volume	503
Issue	1
Pages	254-269
DOI	https://doi.org/10.1093/mnras/stab336
Keywords	binaries: general; stars: individual: TIC 63328020; stars: oscillations
Publisher URL	https://academic.oup.com/mnras/article-abstract/503/1/254/6131847?redirectedFrom=fulltext