Massive star evolution put to the test with Kepler/TESS M. G. Pedersen1, M. Michielsen1, C. Aerts1,2,3 and P. I. Pápics1 1Institute of Astronomy, KU Leuven, Leuven, Belgium | 2Department of Astrophysics/ IMAPP, Radboud University Nijmegen, Nijmegen, The Netherlands | 3MPIA, Heidelberg, Germany
Internal mixing has a high Effect of mixing on the main-sequence evolution of stars with convective cores impact on stellar evolution, Envelope but remains a poorly CBM mixing calibrated quantity for massive stars in particular. y c y y n t t i i e i s s
Asteroseismology allows us c o o i Extent depends f n n f i to probe the stellar interiors, i
E on f H
CBM p
m m g u and determine the efficiency u n L L i
of the internal mixing from x i
the core to the surface of the M
Starting level star. g o defined by Dext L However, the number of O- and f ∈ [0.01, 0.04] H D ∈ [10, 2000] cm2 s-1 B-type stars suitable for CBM p ext asteroseismic modeling has Center Surface Temperature Temperature been limited!
Gravity modes Based on Kepler observations x u l F Gravity mode instability strip Time g s n n i o c i t a a p s l s
u d p
o i d r e t e i P c x
B-type stars e
Pulsation Period f o
# But how about more massive stars that will TESS to Revisiting the Kepler field has lead to a four-fold increase in the become supernova? the rescue! number of B-type stars suitable for asteroseismic modeling Take away We found 4x more B-type pulsators in the Kepler data suitable for asteroseismic modeling compared to previous findings (summary in Szewczuk et al. 2018)
Due to the choice of field-of-view, no stars more
massive than ~8.5 M☉ revealed suitable pulsation modes from the nominal Kepler mission, while K2’s time span is too short.
The TESS continuous viewing zone is therefore crucial for the calibration of stellar structure and evolution models of the most massive stars in the Universe.
Pedersen et al. 2019 Stellar variability detected in 90% of all OB-type stars observed in 2-min cadence by TESS in sectors 1 and 2, covering masses up to ~45 M☉