Frequency and photometric analysis of the short period pulsating star YZ Boo

ABSTRACT In the present paper, analysis of the BVR photometric observations using the 1.88 m telescope of Kottamia Astronomical Observatory (Egypt) is reported. The fundamental mode with many harmonics is determined using Fourier analysis of the light curves. The photometric analysis yielded a value of the period 0d.1040919125, which is in good agreement with the period calculated by previous studies. Seventy-tow new times of maximum light are presented together with180 times from literature. An updated ephemeris for the star is determined and its O-C is presented. Assuming its period is increasing and is changing a little, a near value of (1/P) dP/dt that is determined by previous studies is calculated. Also, the amplitude behaviour is secular at a rate of about Δv = 7.99x10−4 mag./year. By using empirical relations, we determined the physical parameters of YZ Boo as; the radius log(R*/R⊙) = 1.7804 ± 0.044, the bolometric magnitude M bol = 1.71637 ± 0.132, the mass M= 1.943 ± 0.102MΘ, the surface gravity log g = 3.853 ± 0.111, the pulsation constant Q = 0.033 ± 0.002, and distance 544.137 ± 20.565pc.