Discovery of magnetic fields in the β Cephei star ξ 1 CMa and in several Slowly Pulsating B stars ⋆
نویسنده
چکیده
We present the results of a magnetic survey of a sample of eight β Cephei stars and 26 Slowly Pulsating B stars with FORS1 at the VLT. A weak mean longitudinal magnetic field of the order of a few hundred Gauss is detected in the β Cephei star ξ CMa and in 13 SPB stars. The star ξ CMa becomes the third magnetic star among the β Cephei stars. Before our study, the star ζ Cas was the only known magnetic SPB star. All magnetic SPB stars for which we gathered several magnetic field measurements show a field that varies in time. We do not find a relation between the evolution of the magnetic field with stellar age in our small sample. Our observations imply that β Cephei stars and SPBs can no longer be considered as classes of non-magnetic pulsators, but the effect of the fields on the oscillation properties remains to be studied.
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تاریخ انتشار 2006