Nonadiabatic analysis of rosette modes of oscillations in rotating stars and their contribution to angular momentum transport

Abstract

Rosette modes compose a peculiar group of oscillation modes in rotating stars. Although they have been investigated in some theoretical works, it has not been clear yet whether these modes are excited in real stars or not. In order to study this problem, a stability analysis of the modes is performed. It turns out that some rosette modes are unstable due to the kappa mechanism in a model of slowly pulsating B stars. It is also examined how unstable rosette modes can transport angular momentum in stars.