Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Acta Astronomica

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

RR Draconis: An Algol-Type Eclipsing Binary with a Possible Massive Tertiary Companion

Şenavcı H. V., Čeki A., Esmer E. M., Yalçınkaya S., Latković O., Bahar E., Yılmaz M, Bastürk Ö., Özavcı İ., Yörükoğlu O., Selam S. O.

Acta Astronomica

2022

Vol. 72, No. 1

31--53

In this study, we present spectoscopic observations of the eclipsing binary RR Dra carried out with our recently installed T80 telescope in Ankara University Kreiken Observatory and analyze the first radial velocity time series of this system. We simultaneously model TESS light curves along with our radial velocity data to derive absolute parameters of RR Dra system. Additionally, we investigate the period variation of the system using all the available eclipse timings in the literature. In this context, we discuss two possible explanations for the cyclic nature of the eclipse timings: i) light-time effect that corresponds to a high-mass but unseen additional component, ii) magnetic activity of the cooler component. The secular period increase in eclipse timings of RR Dra may be a combination of mass transfer and angular momentum loss, amplified by the presence of circumstellar material.

Orbital Period Analysis of Four Eclipsing Binaries XY Boo, RW Com, MR Del and AK Her

Özavcı İ., Özuyar D., Şenavcı H. V., Yılmaz M, Bahar E., Baştürk Ö., Kılıçoğlu T., Elmaslı A., Çalışkan Ş., İzci D. D., Yörükoğlu O., Selam S. O.

Acta Astronomica

2020

Vol. 70, No. 1

33--52

The orbital period variations of the eclipsing binaries XY Boo, RW Com, MR Del, and AK Her are investigated. This study includes the first orbital period analysis of the detached eclipsing binary MR Del and necessary updates for the remaining stars with addition of new mid-eclipse times calculated from our recent observations carried out at Ankara University Kreiken Observatory. The analysis shows that the period variations may result from mass exchange/loss and a third body for XY Boo, two additional bodies for RW Com, a substellar third component for MR Del, and mass exchange/loss, additional bodies and/or magnetic activity for AK Her. The hypothetical third component of MR Del with an estimated mass of 0.069 M⊙, appears to be very close to the borderline between stars and brown dwarfs.