On the shape of core overshooting in stellar model computations, and asteroseismic tests

Abstract

Slowly pulsating B stars (SPB) and $\gamma$ Dor stars pulsate in high-order gravity (g-) modes. The frequencies of g-modes are sensitive to the detailed structure and evolution history of stars having convective cores. Receding convective cores in OB-type stars leave behind a chemically inhomogenous ${\nabla }_{\mu }>0$ radiative zone. Once a g-mode has radial nodes near the boundaries of these layers, the mode gets trapped and its period deviates from asymptotic period spacing. Careful study of such trapped modes allows constraining the extent of such layers by fitting individual pulsation frequencies. We employ 19 consecuitve dipole g-modes of a very rich Kepler SPB pulsator, KIC 10526294, to demonstrate the power of mode trapping in B-stars in studying the thermal and chemical stratification in the overshooting layer.

4 pages, 4 figures; to appear in the proceedings of "Physics of Evolved Stars 2015 - A conference dedicated to the memory of Olivier Chesneau"

References in corpus (6)

• Probing the properties of convective cores through g modes: high-order g modes in SPB and gamma Doradus stars
• Tight asteroseismic constraints on core overshooting and diffusive mixing in the slowly rotating pulsating B8.3V star KIC 10526294
• Beyond Mixing-length Theory: a step toward 321D
• The internal rotation profile of the B-type star KIC10526294 from frequency inversion of its dipole gravity modes and statistical model comparison
• KIC 10526294: a slowly rotating B star with rotationally split, quasi-equally spaced gravity modes
• Toward a consistent use of overshooting parametrizations in 1D stellar evolution codes

Cited by in corpus (3)

• Evolutionary modelling of subdwarf B stars using MESA with the predictive mixing and convective premixing schemes
• Modeling of multimode radially pulsating High-Amplitude Delta Scuti stars from the OGLE Galactic bulge sample
• Asteroseismic investigation on KIC 10526294 to probe convective core overshoot mixing