Multiple frequencies pulsation of the λ Scuti variable BDS 1269 A

A multi-period analysis has been conducted on the data set of BDS 1269 A made up of the observations obtained by Percy and Rucihski during October 9 to November 6, 1976. In our period analysis, many possible frequencies, which include all frequencies suspected, are selected to constitute the initial frequency estimates. By fitting various combinations of the initial frequencies to the data set, the best one can be determined, which has a minimum number of different frequencies with the lowest residuals. The best fitting frequency solution includes f1=6.22999 cycle d-t, f2 = 6.50840 cycle d-1, f3 = 11.77324 cycle d-1, f4= 9.71369 cycle d-1 and f3= 11.33694 cycled-1. The numeric experiment justifies this five-frequency solution. Based on this solution, a reasonable non-radial rotational splitting pulsation mode is identified, and a rotational velocity v3 = 30 km s-1 is predicted, which tends to agree with the fact that BDS 1269 A is a slowly rotational star.A total of 459 new measurements of four nights during 1987 October 16 to 24 were taken by authors with a Johnson V filter. The fitting with the five-frequency solution to the new data is very good with a residual which is near the uncertainty of the observation.