2. Target Scuti variables in open clusters
In the paper, we focus our attention on Scuti variables on the main sequence. We also restrict our samples to stars belonging to open clusters, for which a good determination of distance is available. Five young clusters are selected: Persei, Pleiades, Hyades, Praesepe and Coma. Detailed information concerning their absolute magnitude and age estimations are listed in Table 1.
Within these five clusters, 30 Scuti variables are found and 28 of them constitute our sample. Two objects, KW284 and 86 Tau, are rejected because their variability is not clear from the three hours light curves available.
The oscillation amplitude is taken to be the highest peak-to-peak measurement in the observed light curve. This is, of course, a very arbitrary way to do the estimation. It is clear that a short time series might induce an underestimation of the amplitude, especially in the presence of beating phenomena due to close frequencies. In order to take this effect into account, we associate with each amplitude estimation a weight corresponding to the length of the time series and list them in Table 1, where number 3 represents time series longer than 20 hours, 2 represents time series between 4 and 20 hours and 1 represents time series shorter than 4 hours.
© European Southern Observatory (ESO) 1999
Online publication: March 18, 1999