Investigation of the stability of the extreme low mass ratio contact binaries SX Crv and XX Sex, which are analysed photometrically


YILDIRIM M.

Advances in Space Research, 2024 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2024
  • Doi Numarası: 10.1016/j.asr.2024.07.068
  • Dergi Adı: Advances in Space Research
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Artic & Antarctic Regions, Communication Abstracts, Compendex, INSPEC, MEDLINE, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Binaries, Eclipsing - stars, Fundamental parameters - stars, Individuals (SX Crv and XX Sex)
  • Çanakkale Onsekiz Mart Üniversitesi Adresli: Evet

Özet

The photometric analyses of the extreme low mass ratio contact binaries SX Crv and XX Sex were conducted in detail. Light curves of SX Crv and XX Sex were retrieved from TESS, and light curve analyses were performed simultaneously with radial velocities. The mass ratios for SX Crv and XX Sex were calculated as 0.077(1) and 0.099(2). The masses of the primary components account for about 90% of the total masses of the systems and were determined to be 1.256(48) M⊙ and 1.337(37) M⊙ for SX Crv and XX Sex, respectively. It has been observed that the orbital periods of both systems have increased. The orbital period change rate of SX Crv has been calculated to be 0.39 s per century, while that of XX Sex has been calculated to be 2.68 s per century. The orbital angular momentum (Jo) determined for both systems is more than 3 times the spin angular momentum (Js), and it can be said that the SX Crv and XX Sex systems are stable. The calculated instability separation (ains.) and instability mass ratio (qins.) values for both systems are smaller than those obtained in the analyses, which supports the stability. The estimated ages of the systems are 7.4 Gyr for SX Crv and 3.9 Gyr for XX Sex. logMtot – logJ and logTeff – logL diagrams were also interpreted to better understand the evolution of the extreme low mass ratio contact binaries.