Discovery of a pre-cataclysmic binary with unusual chromaticity of the eclipsed white dwarf by the GPX survey

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Krushinsky V., Benni P., Burdanov A., Antokhin I., Antokhin E., Jehin E., ...Daha Fazla

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.493, sa.4, ss.5208-5217, 2020 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 493 Sayı: 4
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1093/mnras/staa547
  • Dergi Adı: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Applied Science & Technology Source, Communication Abstracts, INSPEC, Metadex, zbMATH, DIALNET, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.5208-5217
  • Anahtar Kelimeler: binaries: close, binaries: eclipsing, stars: low-mass, white dwarfs, COMMON-ENVELOPE BINARIES, MAIN-SEQUENCE BINARIES, STAR LIGHT, SKY SURVEY, PHOTOMETRY, EVOLUTION, SEARCH, SDSS
  • Ankara Üniversitesi Adresli: Evet

Özet

We report the discovery of a relatively bright eclipsing binary system, which consists of a white dwarf (WD) and a main-sequence K7 star with clear signs of chromospheric and spot activity. The light curve of this system shows similar to 0.2 mag ellipsoidal variability with a period of 0.297549 d and a short total eclipse of the WD. Based on our analysis of the spectral and photometric data, we estimated the parameters of the system. The K7V star is tidally deformed but does not fill its Roche lobe (the filling factor is about 0.86). The orbital inclination is i = 73 degrees.1 +/- 0 degrees.2, and the mass ratio is q = M-2/M-1 approximate to 0.88. The parameters of the K7V star are M-2 approximate to 0.64 M-circle dot, R-2 = 0.645 +/- 0.012R(circle dot), and T-2 approximate to 4070 K. The parameters of the WD are M-1 approximate to 0.72M(circle dot), R-1 = 0.013 +/- 0.003R(circle dot), and T-1 = 8700 +/- 1100 K. Photometric observations in different bands revealed that the maximum depth of the eclipse is in the SDSS r filter, which is unusual for a system of a WD and a late main-sequence star. We suspect that this system is a product of the evolution of a common-envelope binary star, and that the WD accretes the stellar wind from the secondary star (the so-called low-accretion-rate polar, hereafter LARP).