J 2019

Properties and nature of Be stars 31. The binary nature, light variability, physical elements, and emission-line changes of HD 81357

KOUBSKY, P., P. HARMANEC, M. BROZ, L. KOTKOVA, S. YANG et. al.

Základní údaje

Originální název

Properties and nature of Be stars 31. The binary nature, light variability, physical elements, and emission-line changes of HD 81357

Autoři

KOUBSKY, P. (garant), P. HARMANEC, M. BROZ, L. KOTKOVA, S. YANG, H. BOZIC, D. SUDAR, Y. FREMAT, D. KORCAKOVA, Viktor VOTRUBA (203 Česká republika, domácí), P. SKODA, M. SLECHTA a D. RUZDJAK

Vydání

ASTRONOMY & ASTROPHYSICS, LES ULIS CEDEX A, EDP SCIENCES S A, 2019, 1432-0746

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10308 Astronomy

Stát vydavatele

Francie

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 5.636

Kód RIV

RIV/00216224:14310/19:00113465

Organizační jednotka

Přírodovědecká fakulta

UT WoS

000485215200002

Klíčová slova anglicky

binaries: close; binaries: spectroscopic; stars: emission-line Be; stars: fundamental parameters; stars: individual: HD 81357

Štítky

Změněno: 11. 5. 2020 10:37, Mgr. Marie Šípková, DiS.

Anotace

V originále

Reliable determination of the basic physical properties of hot emission-line binaries with Roche-lobe filling secondaries is important for developing the theory of mass exchange in binaries. It is not easy, however, due to the presence of circumstellar matter. Here, we report the first detailed investigation of a new representative of this class of binaries, HD 81357, based on the analysis of spectra and photometry from several observatories. HD 81357 was found to be a double-lined spectroscopic binary and an ellipsoidal variable seen under an intermediate orbital inclination of similar to(63 +/- 5)degrees, having an orbital period of 33.(d)77445(41) and a circular orbit. From an automated comparison of the observed and synthetic spectra, we estimate the component's effective temperatures to be 12930(540) K and 4260(24) K. The combined light-curve and orbital solutions, also constrained by a very accurate Gaia Data Release 2 parallax, give the following values of the basic physical properties: masses 3.36 +/- 0.15 and 0.34 +/- 0.04 M-circle dot(N), radii 3.9 +/- 0.2 and 13.97 +/- 0.05 R-circle dot(N), and a mass ratio 10.0 +/- 0.5. Evolutionary modelling of the system including the phase of mass transfer between the components indicated that HD 81357 is a system observed in the final slow phase of the mass exchange after the mass-ratio reversal. Contrary to what has been seen for similar binaries like AU Mon, no cyclic light variations were found on a time scale an order of magnitude longer than the orbital period.