Variable stars study with TESS

Examination of all chemically peculiar stars observed by TESS resulted in the discovery of 199 Ap stars that pulsate as {delta} Sct or {gamma} Dor variables. The fraction of pulsating Ap stars is the same as the fraction of pulsating chemically normal stars.

There is no distinct separation in frequency or radial order between chemically peculiar {delta} Sct stars and roAp stars. In fact, all the features that originally distinguished roAp from {delta} Sct stars in the past have disappeared. There is no reason to assume that the high frequencies in roAp stars are driven by a different mechanism from the high frequencies in chemically normal stars.