Nonradial pulsation of the delta Scuti star BU CANCRI in the Praesepe cluster.

Abstract

Multisite photoelectric photometry of the δ Scuti star BU Cnc in the Prasepe cluster was obtained during 1989 February at five observatories on three continents. Five pulsation frequencies (19.76, 17.36, 16.69, 18.62 and 19.87 cycles d −1 ) with millimag amplitudes were detected with a signal/noise amplitude ratio ≥ 4.0. An additional frequency at 23.91 cycles d −1 might also exist. The solution fits the observations to ± 2.6 millimag. The pulsation modes can be identified with p 3±1 modes with at least two different values. Only up to two ( = 0) radial modes are possible