Slowly Pulsating B Stars

Abstract

We discuss two new slowly pulsating B stars for which it can be convincingly shown that they are multiperiodic variables. The group now contains ten confirmed and likely multiperiodic mid-B stars with periods between 0.7 and 4.4 days. The multiperiodicity and the length of the periods point to g-mode pulsations. The very high order of the modes implies that the modes are excited in the core or in the very outer layers of the star. A recently proposed mechanism, in which both the inner and outer layers intervene, is discussed.