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

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.
1 September 2022 Institute of Physics

Astrophysical Journal
2022 #936 Issue 2

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 _⊙).

Text of the article Перейти на текст статьи

Al-Farabi Kazakh National University, Al-Farabi Ave., 71, Almaty, 050040, Kazakhstan
Department of Physics and Astronomy, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, 27402-6170, NC, United States
Central Astronomical Observatory, the Russian Academy of Sciences at Pulkovo, Pulkovskoye shosse 65-1, St. Petersburg, 196140, Russian Federation
Fesenkov Astrophysical Institute, Observatory, 23, Almaty, 050020, Kazakhstan
Universidad Nacional Autónoma de México, Instituto de Astronomía, AP 106 BC, Ensenada, 22800, Mexico
Special Astrophysical Observatory, The Russian Academy of Sciences, Nizhnyj, Zelenchukskiy region, Karachai-Cherkessian Republic, Arkhyz, 369167, Russian Federation
Canada-France-Hawaii Telescope Corporation, 65-1238 Mamalahoa Hwy, Kamuela, 96743, HI, United States
Crimean Astrophysical Observatory, Scientific Research Institute, Nauchny, 298409, Russian Federation
V.V. Sobolev Astronomical Institute of the St.-Petersburg State University, St.-Petersburg, 198504, Russian Federation
Kookoosint Scientific, 1530 Calle Portada, Camarillo, 93010, CA, United States
Center for Astrophysics &, Space Science University of California, San Diego, 9500 Gilman Dr La Jolla, 92093, CA, United States
Alabaster Scientific, P.O. Box 120, Irvington, 22480, VA, United States

Al-Farabi Kazakh National University
Department of Physics and Astronomy
Central Astronomical Observatory
Fesenkov Astrophysical Institute
Universidad Nacional Autónoma de México
Special Astrophysical Observatory
Canada-France-Hawaii Telescope Corporation
Crimean Astrophysical Observatory
V.V. Sobolev Astronomical Institute of the St.-Petersburg State University
Kookoosint Scientific
Center for Astrophysics &
Alabaster Scientific

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026