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

Year 2017, Volume: 19 Issue: 3, 84 - 88, 07.12.2017

Burcu Özkardeş , Gökçe Zeynep Özalp

https://doi.org/10.25092/baunfbed.363771

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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