53 Persei : a slowly pulsating B star ?
نویسنده
چکیده
A new investigation of the behaviour of the star 53 Per was performed. New photometric observations allow to confirm twodominant periods p1=2.16 d, p2= 1.67 d.A third one p3= 3.64 d is detected. These long period variations are present in our radial velocities data and in old equivalent width data. The amplitude of the p1 = 2.16 d period increases from 1977 to 1991, while the amplitude of the 1.67 d period remains constant. Considering the observational characteristics of the star since 1997, 53 Per clearly belongs to the Slowly Pulsating B stars group as defined by Waelkens (1991) and North & Paltani (1994).
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