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Title: 20 s Cadence TESS Photometry of HR 8799

We analyzed 20 s cadence Transiting Exoplanet Survey Satellite time-series photometry of the exoplanet host star HR 8799 collected in Sector 56. The amplitude spectrum shows Gamma Doradus (γ Dor) pulsations consistent with previous space-based photometry from MOST. Assuming that HR 8799 is a representative ofγ Dor stars in the Kepler sample, the dominant dipole mode at 1.98 cycles day−1implies a core rotation period of ∼0.7 day, which combined withvsiniand stellar radius measurements would result in a preliminary stellar inclination of ∼28° assuming rigid rotation. We find no significant residual photometric variation after removing the pulsation signal aside from a ∼9 days trend that is likely a systematic effect or an artifact from performing aggressive frequency subtraction in the presence of red noise.

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Publication Date:
Journal Name:
Research Notes of the AAS
Page Range or eLocation-ID:
Article No. 2
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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