Details

Autor(en) / Beteiligte

• Nodyarov, A. S.
• Miroshnichenko, A. S.
• Khokhlov, S. A.
• Zharikov, S. V.
• Manset, N.
• Klochkova, V. G.
• Grankin, K. N.
• Arkharov, A. A.
• Efimova, N.
• Klimanov, S.
• Larionov, V. M.
• Rudy, R. J.
• Puetter, R. C.
• Perry, R. B.
• Reva, I. V.
• Omarov, C. T.
• Kokumbaeva, R. I.

Titel

Toward Understanding the B[e] Phenomenon. IX. Nature and Binarity of MWC645

Ist Teil von

• The Astrophysical journal, 2022-09, Vol.936 (2), p.129

Ort / Verlag

Philadelphia: The American Astronomical Society

Erscheinungsjahr

2022

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Abstract We present the results of optical and near-IR spectroscopy and multicolor photometry of the emission-line star MWC 645, which exhibits the B[e] phenomenon. The presence of positionally variable absorption lines of a cool star detected for the first time indicates that the object is a binary system. Using a combination of the photometric and spectroscopic data as well as the Gaia EDR3 distance ( D = 6.5 ± 0.9 kpc), we disentangled the components’ contributions and estimated their surface temperatures and luminosities (18, 000 ± 2000 K and 4250 ± 250 K, log L / L ⊙ = 4.0 ± 0.5 and 3.1 ± 0.3 for the hot and cool components, respectively). Quasi-cyclic short-period (months) and long-period (∼4 yr) photometric variations were detected in both optical and near-IR regions, and are most likely due to variable circumstellar extinction. Our analysis suggests that MWC 645 is a member of the FS CMa group. The object’s properties can be described by an evolutionary model of a close binary system that currently undergoes a nonconservative mass transfer between intermediate-mass stars (e.g., 7 M ⊙ + 2.8 M ⊙ ).