A. S. Nodyarov

Al-Farabi Kazakh National University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

АС

А. С. Мирошниченко

University of North Carolina at Greensboro

S. A. Khokhlov

Al-Farabi Kazakh National University

S. V. Zharikov

Al-Farabi Kazakh National University

N. Manset

Canada–France–Hawaii Telescope

ВГ

В. Г. Клочкова

Special Astrophysical Observatory

V. M. Larionov

St Petersburg University

Ashish Raj

Indian Centre for Space Physics

S. A. Klimanov

Pulkovo Observatory

S. Drew Chojnowski

Ames Research Center

S. Danford

University of North Carolina at Greensboro

Cooperative Institutions

Al-Farabi Kazakh National University

Fesenkov Astrophysical Institute

Pulkovo Observatory

Isaac Newton Institute

Russian Academy of Sciences

St Petersburg University

Odesa I. I. Mechnikov National University

Institute of Applied Astronomy

Special Astrophysical Observatory

University of North Carolina at Greensboro

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

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

The Astrophysical Journal (2022)

A. S. Nodyarov А. С. Мирошниченко S. A. Khokhlov S. V. Zharikov N. Manset

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 ⊙ ).

Extinction (optical mineralogy)

Variable star

Be star

10.3847/1538-4357/ac87a1

Cite

Citations (4)

Properties of Galactic B[e] Supergiants. X. Refined Orbit and Fundamental Parameters of the HD 327083 Binary System

The Astrophysical Journal (2024)

A. S. Nodyarov А. С. Мирошниченко S. A. Khokhlov S. V. Zharikov Aldiyar Agishev

Abstract HD 327083 is a binary system that consists of two supergiant components and exhibits the B[e] phenomenon. In this paper, we report the determination of a new set of the system’s fundamental parameters using a combination of photometric and spectroscopic data as well as the Gaia EDR3 distance. We found that the orbital period of the system is 107.68 ± 0.02 days. The spectral line content implies the effective temperatures of ≈7000 K and 25,400 ± 1400 K, while the photometric variations are consistent with the radii of ≈106 R ⊙ and ≈10 R ⊙ for the cool and hot components, respectively. The absorption lines of the cool component show a radial velocity semiamplitude of 48.3 ± 1.7 km s −1 , similar to that of the emission lines that originate around the hot component. The inclination of the system to the line of sight is 47 − 20 + 17 °. Modeling of the system's evolutionary history suggests that the components have masses of ∼12.5 M ⊙ and currently undergo mass transfer between them. This configuration, which takes in heating of the surface of the cool component by the radiation from the hot one, can reproduce the photometric and spectroscopic data and is in agreement with previous infrared observations of the circumbinary disk. The results of this study further confirm the hypothesis that the reason for the presence of the B[e] phenomenon in most objects is a consequence of the evolution of various binary systems.

Line (geometry)

10.3847/1538-4357/ad4a63

Cite

Citations (0)

HIGH-RESOLUTION SPECTROSCOPY OF THE B[e] STAR MWC 645

Odessa Astronomical Publications (2021)

A. S. Nodyarov А. С. Мирошниченко S. A. Khokhlov S. V. Zharikov N. Manset

Optical high-resolution spectroscopic observations of the emission-line star MWC645 are presented. The spectrum exhibits strong variable double-peaked Balmer emission lines as well as low-excitation emission lines of FeII, [FeII], and [OI] which are signatures of the B[e] phenomenon, while lines of helium have not been found. In addition to the emission lines, for the first time we identified absorption lines of neutral metals (e.g., LiI 6708 A, CaI 6717 A, and a number of FeI and TiI lines) that indicate the presence of a cool component in the system. The heliocentric radial velocity measured in our best spectrum was found to be −65.1±1.0 kms −1 for the emission lines and −23.2±0.4 kms −1 for the absorption lines. Using a combination of photometric and spectroscopic data as well as the Gaia EDR3 distance (D=6.5±0.9 kpc), we disentangled the component contributions and estimated their temperatures and luminosities (∼15000 K and ∼4000 K, log L/L ? = 3.8±0.2 and 2.8±0.2 for the hot and cool component, respectively).

Balmer series

Line (geometry)

Radial velocity

10.18524/1810-4215.2021.34.244321

Cite

Citations (1)

REFINED PHYSICAL PROPERTIES OF THE HD327083 BINARY SYSTEM

Odessa Astronomical Publications (2022)

A. S. Nodyarov А. С. Мирошниченко S. A. Khokhlov S. V. Zharikov N. Manset

HD327083 is a member of a small group of supergiants exhibiting the B[e] phenomenon. It was found to be a binary system with an early-B and an early-F supergiant components. However the fundamental and orbital parameters of the system were not accurately known. We determined a new set of the system parameters that include the orbital period and the components’ masses using a combination of photometric and spectroscopic data. A new orbital period of 107.7 days was found from both the spectral line positional variations and the visual light curve. Absorption lines of the cool component show a radial velocity semi-amplitude of 48.3 kms −1 , similar to that of emission lines that originate around the hot component. The system shows partial eclipses. We estimated the components’ masses to be nearly equal and close to 6-8 M ? . The masses turned out to be smaller then the evolutionary masses that may be a consequence of a recent mass-transfer.

Orbital period

Radial velocity

Component (thermodynamics)

Line (geometry)

Mass ratio

Orbital inclination

Orbital elements

10.18524/1810-4215.2022.35.268106

Cite

Citations (1)

Recent Progress in Finding Binary Systems with the B[e] Phenomenon

Galaxies (2023)

А. С. Мирошниченко S. V. Zharikov N. Manset S. A. Khokhlov A. S. Nodyarov

This paper describes recent studies of the FS CMa-type objects, a group of stars showing the B[e] phenomenon defined in 2007. The objects exhibit strong emission-line spectra with both permitted and forbidden lines suggesting the presence of a B-type star as well as strong IR excesses due to radiation of circumstellar dust. These properties are hard to explain in the framework of the evolution of single stars with luminosities between ~300 and ~30,000 L⊙ typical of most B-type stars. We explore the hypothesis that the gaseous-and-dusty envelopes of FS CMa objects are due to either earlier or ongoing mass transfer between the binary system components. It is hard to detect the secondary components in these systems because of veiling and distortions by the circumstellar matter because of the relative faintness of the companions. Nevertheless, we detected regular radial velocity variations of the spectral lines in MWC 728, 3 Pup, and AS 386 and we found absorption lines typical of cool stars in the spectra of MWC 645, AS 174, and several other objects. The diversity of the secondary components in FS CMa objects is discussed in the context of non-conservative binary evolution.

Line (geometry)

Radial velocity

Circumstellar disk

10.3390/galaxies11010036

Cite

Citations (2)