A beta Cephei pulsator and a changing orbital inclination in the high-mass eclipsing binary system VV Orionis

TL;DR

This study analyzes the high-mass eclipsing binary VV Ori, revealing pulsations influenced by tidal forces and a decreasing orbital inclination likely caused by a third body, with precise mass measurements for both stars.

Contribution

It provides the first precise mass measurements for both pulsating stars in VV Ori and reports on the tidal perturbation of pulsations and changing orbital inclination.

Findings

Detection of 51 significant oscillation frequencies.

Identification of tidally perturbed pulsations with orbital frequency separations.

Observation of decreasing orbital inclination likely due to a third body.

Abstract

We present an analysis of the high-mass eclipsing binary system VV Ori based on photometry from the TESS satellite. The primary star (B1V, 9.5 Msun) shows beta Cephei pulsations and the secondary (B7V, 3.8 Msun) is possibly a slowly-pulsating B star. We detect 51 significant oscillation frequencies, including two multiplets with separations equal to the orbital frequency, indicating that the pulsations are tidally perturbed. We analyse the TESS light curve and published radial velocities to determine the physical properties of the system. Both stars are only the second of their pulsation type with a precisely-measured mass. The orbital inclination is also currently decreasing, likely due to gravitational interactions with a third body.