β Lyrae türü örten çift yıldız LL Com: Işık eğrisi analizi ve yörünge dönemi değişimi

Abstract

Bu çalışmada, ilk kez, β Lyrae türü (EB) olarak sınıflandırılmış örten çift yıldız LL Com (GSC 02535-00670; V = 12^m.39; P = 0.40692 gün)’un ışık eğrisi analizi ve yörünge dönemi değişimi sunulmaktadır.  Sistemin, SuperWASP arşivinde yer alan fotometrik gözlem verisi Wilson – Devinney (W-D) yöntemiyle analiz edilerek fotometrik kütle oranı belirlenmiş ve buradan bileşen yıldızların tahmini mutlak parametreleri hesaplanmıştır.  Sistemin literatürde bulunan minimum ışık zamanları ile bu çalışmada elde edilen tutulma zamanları kullanılarak O-C analizi yapılmış ve yörünge döneminin değişimine neden olan fiziksel mekanizmalar tartışılmıştır.

Keywords

• Çift yıldız,örten çift yıldız,β Lyrae türü,LL Com

β Lyrae type eclipsing binary star LL Com: Light curve analysis and orbital period change

Abstract

In this study, light curve analysis and orbital period variation of the eclipsing binary star LL Com (GSC 02535-00670; V = 12^m.39; P = 0.40692 day) classified as β Lyrae type (EB) is presented for the first time.  The photometric observation data in the SuperWASP archive were analyzed by Wilson – Devinney (W-D) method, and the photometric mass ratio was determined.  Hence, the estimated absolute parameters of the component stars were calculated. The O-C analysis was performed using all minima times of the system in the literature with the eclipse minima times obtained from this study and the physical mechanism causing the orbital period change was discussed.

Keywords

• Binary star,eclipsing binary star,β Lyrae type,LL Com

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