Rosette modes of oscillations of rotating stars caused by close degeneracies. II. Nonaxisymmetric modes

Our previous analysis of axisymmetric rosette modes of oscillations in rigidly rotating stars is extended to nonaxisymmetric modes. The rosette modes, which have peculiar eigenfunctions, are formed by interaction among g modes having close frequencies with the particular rules regarding radial orders and spherical degrees. Such interaction is caused by the second-order effect of the Coriolis force. For nonaxisymmetric cases, the first-order rotation effect, which is proportional to the azimuthal order and the rotation frequency, tends to work against the formation of rosette modes. It is, however, found that the poisoning effect is not so serious in many cases that nonaxisymmetric rosette modes are present. The difference between prograde and retrograde modes is discussed.