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

Yıl 2017, Cilt: 19 Sayı: 3, 84 - 88, 07.12.2017

Burcu Özkardeş Gökçe Zeynep Özalp

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

Öz

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.

Anahtar Kelimeler

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

Öz

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.

Anahtar Kelimeler

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

Kaynakça

• Kurochkin, N.E., New variable stars in SA 57, Peremennye Zvezdy, 409-417, (1959).
• Frank, P., Moschner, J. ve Moschner, W., NSV 6177: First elements and lightcurve, Information Bulletin on Variable Stars, No. 4386, (1996).
• Kazaovets, E.V., Samus, N.N. ve Durlevich, O.V., The 75th name-list of variable stars, Information Bulletin on Variable Stars, No. 4870, (2000).
• Hoffman, D.I., Harrison, T.E., Coughlin, J.L., McNamara, B.J., Holtzman, J.A., Taylor, G.E. ve Vestrand, W.T., New β Lyrae and Algol candidates from the Northern Sky Variability Survey, The Astronomical Journal, 136, 1067-1078, (2008).
• Gaia Collaboration; Brown, A. G. A. et al., Gaia Data Release 1. summary of the astrometric, photometric, and survey properties, Astronomy & Astrophysics, 595, 1-23, (2016).
• O-C gateway Database of times of minima (E) and maxima (RR), http://var2.astro.cz/ocgate/, (19.05.2017).
• Kwee, K.K. ve van Woerden, H., A method for computing accurately the epoch of minimum of an eclipsing variable, Bulletin of the Astronomical Institutes of the Netherlands, 12, 327-330, (1956).
• Kreiner, J.M., Up-to-date linear elements of eclipsing binaries, Acta Astronomica, 54, 207-210, (2004).
• Zasche, P., Liakos, A., Niarchos, P., Wolf, M ve Gazeas, K., Period changes in six contact binaries: WZ And, V803 Aql, DF Hya, PY Lyr, FZ Ori, and AH Tau, New Astronomy, 14, 2, 121-128, (2009).
• SuperWASP Wide Angle Search for Planets, www.superwasp.org, (19.05.2017).
• Wilson, R.E. ve Devinney, E.J., Realization of accurate close-binary light curves: application to MR Cygni, The Astronomical Journal, 166, 605-619, (1971).
• Prsa, A., Matijevic, G., Latkovic, O., Vilardell, F. ve Wils, P., PHOEBE: PHysics Of Eclipsing BinariEs, Astrophysics Source Code Library, record ascl:1106.002, (2011).
• Eker, Z., Bilir, S., Yaz, E., Demircan, O. ve Helvacı, M., New absolute magnitude calibrations for W Ursa Majoris type binaries, Astronomische Nachrichten, 330, 1, 68-76, (2009).
• Drilling, J.S. ve Landolt, A.U., Allens Astrophysical Quantities, 4th. Edition, AIP Press., Springer NY, (2000).
• van Hamme, W., New limb-darkening coefficients for modeling binary star light curves, The Astronomical Journal, 106, 2096-2117, (1993).
• Rucinski, R.M., The proximity effects in close binary systems. II. the bolometric reflection effect for stars with deep convective envelopes, Acta Astronomica, 19, 245-254, (1969).
• von Zeipel, H., Radiative equilibrium of a double-star system with nearly spherical components, Monthly Notices of the Royal Astronomical Society, 84, 702-721, (1924).
• Bradstreet, D.H. ve Steelman, D.P., Binary Maker 3.0 - an interactive graphics-based light curve synthesis program written in java, American Astronomical Society, 201st AAS Meeting, 34, 1224, (2002).
• Pecaut, M.J. ve Mamajek, E.E., Intrinsic colors, temperatures, and bolometric corrections of pre-main-sequence stars, The Astronomical Journal Supplement Series, 208:9, 1-22, (2013).