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تسجيل مستخدم جديدPTF1J2224+17: a short-period, high-field polar
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We present time-resolved photometry of the cataclysmic variable (CV) PTF1J2224+17 obtained during 4 nights in October 2018 and January 2019 from Inastars observatory. The object is variable on a period of 103.82 min. Archival Catalina Real-Time Transient Survey (CRTS), PTF, and ZTF-data show frequent changes between high and low states. Based on its photometric properties and the cyclotron humps in the identification spectrum the object is certainly classified as an AM Herculis star (or polar) with a likely magnetic field strength of B ~ 65 MG. Its accretion duty cycle was estimated from nine years of photometric monitoring to be about 35 %.
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