Herbert Pablo, Steven D. Kawaler, M. D. Reed, S. Bloemen, S. Charpinet, H. Hu, J. Telting, R. H. Østensen, A. S. Baran, E. M. Green, J. J. Hermes, T. Barclay, S. J. O'Toole, Fergal Mullally, D. W. Kurtz, J. Christensen-Dalsgaard, Douglas A. Caldwell, Jessie L. Christiansen, K. Kinemuchi
We report on extended photometry of two pulsating sdB stars in close
binaries. For both cases, we use rotational splitting of the pulsation
frequencies to show that the sdB component rotates much too slowly to be in
synchronous rotation. We use a theory of tidal interaction in binary stars to
place limits on the mass ratios that are independent of estimates based on the
radial velocity curves. The companions have masses below 0.26 M\odot. The
pulsation spectra show the signature of high-overtone g-mode pulsation. One
star, KIC 11179657, has a clear sequence of g-modes with equal period spacings
as well as several periodicities that depart from that trend. KIC 02991403
shows a similar sequence, but has many more modes that do not fit the simple
pattern.
View original:
http://arxiv.org/abs/1202.3649
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