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arXiv · 0811.0568

Variation of the Light and Period of the Magnetic Cataclysmic Variable Am Her

Belinda Kalomeni·Kadri Yakut
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Abstract

Ground-based long-term optic variability of AM Her, covering the period between 2003-2008, has been conducted to study the features seen in both low and high states of the system. Low-state analysis shows the presence of short-term, low-amplitude light variations of about 0.02-0.03 mag with a mean power time between 16 s and 226 s. Brightness variations on the order of 0.7--2 mag, which could be due to the stellar activity of the component in the system, are also detected. A total of 30 years times of minimum light given in the literature are combined with nine times of minima obtained in this study. We represented the (observed--calculated) diagram by a parabolic curve and also by two broken lines. Under the assumption of a parabolic variation, we estimate an increase in period, dP/dt=7.5(1.2)x10^{-9} days yr^{-1}, with a mass transfer rate of dM/dt = 8(2)x10^{-9} M_{\odot} yr^{-1}, in agreement with the previous findings by a different method.

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Belinda Kalomeni, Kadri Yakut. 2008-11-04. Variation of the Light and Period of the Magnetic Cataclysmic Variable Am Her. https://doi.org/10.1088/0004-6256%2F136%2F6%2F2367

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