Rotational modulation in TESS B stars

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Balona L. A., Handler G., Chowdhury S., ÖZUYAR D., Engelbrecht C. A., Mirouh G. M., ...Daha Fazla

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.485, sa.3, ss.3457-3469, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 485 Sayı: 3
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1093/mnras/stz586
  • Dergi Adı: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.3457-3469
  • Anahtar Kelimeler: stars: early-type, stars: oscillations, stars: rotation, HOT MASSIVE STARS, MAGNETIC-FIELDS, FUNDAMENTAL PARAMETERS, DIFFERENTIAL ROTATION, SPECTROSCOPIC SURVEY, CHEMICALLY PECULIAR, CALIBRATION, TEMPERATURE, PHOTOMETRY, SYSTEM
  • Ankara Üniversitesi Adresli: Evet

Özet

Light curves and periodograms of 160 B stars observed by the Transiting Exoplanet Survey Satellite (TESS) space mission and 29 main-sequence B stars from Kepler and K2 were used to classify the variability type. There are 114 main-sequence B stars in the TESS sample, of which 45 are classified as possible rotational variables. This confirms previous findings that a large fraction (about 40 per cent) of A and B stars may exhibit rotational modulation. Gaia DR2 parallaxes were used to estimate luminosities, from which the radii and equatorial rotational velocities can be deduced. It is shown that observed values of the projected rotational velocities are lower than the estimated equatorial velocities for nearly all the stars, as they should be if rotation is the cause of the light variation. We conclude that a large fraction of main-sequence B stars appear to contain surface features which cannot likely be attributed to abundance patches.