7. Other short periods?
Using various segments of photometric data prewhitened for variations on timescales of weeks and longer, I checked on the presence of periods in the range from 0 4 to 3 0. I found that the 1986-1987 observations by Balona et al. (1987) can indeed be best reconciled with a period of 1 4749 0 0029 and a semi-amplitude 0 0045 which is only about 1.5 times higher than the semi-amplitudes detected for the constant comparison stars. However, this periodicity cannot be detected in another subset, also from the same phase of strong emission (around HJD 2447900), where a period of 2 7428, reminiscent of the period advocated by Clarke (1990), is formally detected.
© European Southern Observatory (ESO) 1998
Online publication: May 15, 1998