Internal rotation and mixing in the massive star HD192575
Date of Archiving2021
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Key wordsStellar; Astrophysics; Asteroseismology; Massive stars
The evolution of high mass stars (>8M_sun) is strongly dictated by their interior structure, specifically the mixing processes near the core and in the surrounding envelope. Asteroseismology can open up these stellar interiors but unfortunately Kepler did not provide any high-mass stars with identified modes for this endeavour. The TESS space mission is remedying this by observing a large number of high-mass stars allowing us to construct an asteroseismic sample of OB pulsators and open up the way to their asteroseismic sounding.In this poster we present a detailed analysis of the high-mass pulsator HD192575 (B0.5 V) using its 1-year TESS light curve. HD192575 is among the first of its variability class to be observed uninterruptedly during such a long time and the resulting high frequency precision of the measured pulsations allows for in-depth modelling. In our novel modelling strategy we use a maximum likelihood estimator which incorporates correlations among the parameters and theoretical uncertainties due to unknown input physics of stellar models. This allows us to derive a precise mass, internal mixing, and age from zonal modes, as well as its interior rotation from detected rotationally split multiplets of low-degree modes.