Verlag der Österreichischen Akademie der Wissenschaften
157
260
No
International
1021-2043
Wien
Austria
Wroclaw Helas workshop
du 23 au 27 juin 2008
Uniwersytet Wroclawski
Wroclaw
Pologne
[en] Since their discovery eleven years ago, short-period pulsating sdB stars have proved their potential for quantitative asteroseismological studies. We have recently updated our astero- seismic diagnostic tools in order to incorporate the effects of stellar rotation on pulsations, assuming various internal rotation laws. It is possible, with these new tools, to determine the internal rotation profile of two short-period pulsating sdB stars residing in close binary systems, namely Feige 48 and PG 1336 -018. They exhibit orbital periods of 9.024 h and 2.424 h respectively, as measured from spectroscopy. For the two stars, we show that spin-orbit synchronism is reached from the surface down to ˜ 0.22 R∗ and 0.55 RxE2x88x97 , respectively. The rotation of deeper layers cannot be inferred with the type of modes p-modes observed in short-period pulsating sdB stars. These results can potentially provide new elements to test tidal friction theories, particularly the angular momentum transport, in close binary systems.
[Université de Toulouse/Université de Montréal (UdeM) > > > >]
