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تسجيل مستخدم جديدTYC 5353-1137-1: an enigmatic Double Periodic Variable of semiregular amplitude
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نشر من قبل
Jaime Andr\\'es Rosales Guzm\\'an
تاريخ النشر
2018
مجال البحث
فيزياء
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English
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We have performed a new search for DPVs of short period in the ASAS catalog (Pojmanski, G., 1997), focusing on those stars with orbital periods between 2 to 3 days which also show variations in their brightness. From a total of 244 objects, we have found another candidate to DPV, one whose mean brightness is gradually decreasing. By fitting a 3rd order polynomial to the mean magnitude and then moving it to zero for a second analysis, a gradual decrease over 2500 days was revealed. During the last 1000 days of this decrease, a 42% increase in the variation between the minimum and maximum values of the magnitude was observed. We determined the orbital period by using the PDM IRAF software (Stellingwerf 1978) and estimated the errors for the orbital period and long cycle by visual inspection of the light curves phased with trial periods near the minimum of the periodogram given by PDM.
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