Can an underestimation of opacity explain B-type pulsators in the SMC?

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Slowly Pulsating B and β Cephei are κ mechanism driven pulsating B stars. That κ mechanism works since a peak in the opacity due to a high number of atomic transitions from iron-group elements occurs in the area of T ≈ 5.3. Theoretical results predict very few SPBs and no β Cep to be encountered in low metallicity environments such as the Small Magellanic Cloud. However recent variability surveys of B stars in the SMC reported the detection of a significant number of SPB and β Cep candidates. Though the iron content plays a major role in the excitation of β Cep and SPB pulsations, the chemical mixture representative of the SMC B stars such as recently derived does not leave room for a significant increase of the iron abundance in these stars. Whilst abundance of iron-group elements seems reliable, is the opacity in the iron-group elements bump underestimated? We determine how the opacity profile in B-type stars should change to excite SPB and β Cep pulsations in early-type stars of the SMC.