AN LYN - AN UNUSUAL MEDIUM AMPLITUDE DELTA-SCT STAR

Simultaneous uvby beta photometric observations of the medium amplitud e delta Set star AN Lyn have been collected and new times of light max ima have been obtained. The Fourier transform and classical O-C method s are used to analyse the pulsation of this star. The light curves are peculiar in the sense that the descending branches are steeper than t he ascending ones. Amplitude variations are shown to be present from s eason to season. The analysis of the phase shifts between observed lig ht and colour variations suggests that this star is a radial pulsator. In addition, intrinsic b-y, m(1) and c(1) values are also derived and the physical parameters are determined indicating that this variable is a nearly cold and evolved delta Set star showing solar metal abunda nces and pulsating in the second overtone.