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

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 نشر من قبل John Southworth
 تاريخ النشر 2020
  مجال البحث فيزياء
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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.

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