TESS A and B stars and the Maia variables

Whereas it has been assumed that high-frequency pulsations among B-type main-sequence stars are confined to the early B-type {beta} Cephei stars, the observations indicate that high frequencies are to be found over the whole B-star range, eventually merging with {delta} Scuti stars.

The cool B stars pulsating in high frequencies are called Maia variables. It is shown that Maia variables are not rapidly rotating and thus cannot be {beta} Cephei pulsators that appear to have lower temperatures due to gravity darkening. In the region where {beta} Cephei variables are found, the proportion of pulsating stars is larger and amplitudes are higher and a considerable fraction pulsate in a single mode and low rotation rate.