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تسجيل مستخدم جديدPhotometric detection of internal gravity waves in early-type stars observed by CoRoT
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Early-type stars are predicted to excite an entire spectrum of internal gravity waves (IGWs) at the interface of their convective cores and radiative envelopes. Numerical simulations of IGWs predict stochastic low-frequency variability in photometric observations, yet the detection of IGWs in early-type stars has been limited by a dearth of high-quality photometric time series. We present observational evidence of stochastic low-frequency variability in the CoRoT photometry of a sample of O, B, A and F stars. The presence of this stochastic low-frequency variability in stars across the upper main-sequence cannot be universally explained as granulation or stellar winds, but its morphology is found to be consistent with predictions from IGW simulations.
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Context. Main sequence stars with a convective core are predicted to stochastically excite Internal Gravity Waves (IGWs), which effectively transport angular momentum throughout the stellar interior and explain the observed near-uniform interior rota
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