Rotational Splitting of Pulsating Hot Subdwarfs Observed by TESS

Hot subdwarf B (sdB) stars are stripped red giants with a helium-fusing core. They are thought to form in binaries through Roche lobe overflow and common envelope interactions. Many hot subdwarfs pulsate with gravity and/or acoustic-mode oscillations, and asteroseismological studies of their vibrations can shed light on their interior structures and fundamental parameters like mass and radius. Stellar rotation can also be observed through a “splitting” of pulsation modes in a Lomb Scargle periodogram. Here we analyze high-cadence TESS photometry of several dozen pulsating hot subdwarfs and look for evidence of rotational splitting.