Whole Earth Telescope observations of the DAV white dwarf G226-29

We observed G226-29 for 121 hr in 1992 February and confirm the presence of the three previously identified frequencies close to 109 s. We find no evidence of other pulsation periods down to our noise level of about 0.35 millimodulation amplitudes. The presence of only one triplet pulsation mode in G226-29 and its effective temperature near the blue edge of the instability strip identify the observed triplet of modes near 109 s as rotationally split components of the k = 1, l = 1 mode. With the mode identification, we derived a rotation period of 8.9 hr and an inclination of the pulsation axis of 70°-75° to our line of sight.