Article
Astronomy & Astrophysics
Jakub Klencki, Alina Istrate, Gijs Nelemans, Onno Pols
Summary: Mass transfer in binary systems is influenced by various factors, including the metallicity of the stars involved. This study investigates the impact of metallicity on post-main sequence mass transfer, revealing the existence of two novel types of mass transfer and their implications for the evolution of stars in binary systems. The findings suggest a preference for metal-poor host galaxies for certain types of binary systems and shed light on the formation of black hole mergers.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
K. Sen, N. Langer, D. Pauli, G. Graefener, A. Schootemeijer, H. Sana, T. Shenar, L. Mahy, C. Wang
Summary: Massive star feedback plays a crucial role in the evolution of galaxies, with the most massive stars having the largest impact. This study focuses on the detailed evolutionary models of very massive binaries with Large Magellanic Cloud metallicity. The results reveal four effects that challenge the conventional understanding of binary evolution, particularly related to the proximity of the models to the Eddington limit. The findings highlight the significance of understanding very massive Algol systems in predicting the advanced evolution of such binaries.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
T. Shenar, H. Sana, P. A. Crowther, K. A. Bostroem, L. Mahy, F. Najarro, L. Oskinova, A. A. C. Sander
Summary: In this study, the presence of close stellar companions to the most massive stars known is constrained for the first time through multi-epoch spectroscopy. It is found that only R 136 c is classified as a binary system, while the other stars are likely single. It is inferred that there are no companions with masses greater than or similar to 50 solar masses for R 136 a1, a2, and a3.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Weiguo Peng, Hanfeng Song, Georges Meynet, Andre Maeder, Fabio Barblan, Ruiyu Zhang, Sylvia Ekstromt, Cyril Georgy, Gang Long, Liuyan Zhao, Ying Qin
Summary: The study shows that binary systems are more likely to produce low-luminosity WC stars compared to single stars, and enhanced wind mass loss rates can contribute to the formation of low-luminosity WO stars.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Michael M. Shara, Steve B. Howell, Elise Furlan, Crystal L. Gnilka, Anthony F. J. Moffat, Nicholas J. Scott, David Zurek
Summary: By conducting a speckle imaging survey of the nearest and brightest Wolf-Rayet stars, new close companions were discovered, providing evidence that predicted faint companions to WR stars can now be detected using modern speckle cameras.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Felipe Navarete, Augusto Damineli, Aura E. Ramirez, Danilo F. Rocha, Leonardo A. Almeida
Summary: This study used photometric and astrometric data from Gaia Early Data Release 3 to determine the distance of Westerlund 1 star cluster as 4.06(-0.34)(+0.36) kpc and derived an age of 10.7 +/- 1 Myr for the cluster.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
S. Janssens, T. Shenar, L. Mahy, P. Marchant, H. Sana, J. Bodensteiner
Summary: BAT99 126 is a multiple system with at least four components, including a short-period binary system that is unlikely to evolve into a black hole merger.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
T. Shenar, H. Sana, P. Marchant, B. Pablo, N. Richardson, A. F. J. Moffat, T. Van Reeth, R. H. Barba, D. M. Bowman, P. Broos, P. A. Crowther, J. S. Clark, A. de Koter, S. E. de Mink, K. Dsilva, G. Grafener, I. D. Howarth, N. Langer, L. Mahy, J. Maiz Apellaniz, A. M. T. Pollock, F. R. N. Schneider, L. Townsley, J. S. Vink
Summary: The study revealed R 144 as an eccentric binary comprising two relatively evolved hydrogen-rich Wolf-Rayet stars, with an orbital inclination of 60.4° and dynamical masses of 74 and 69 solar masses. The researchers advocate for future monitoring of R 144 and other massive binaries to address challenges in measuring component masses.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
G. Lenoir-Craig, N. St-Louis, A. F. J. Moffat, H. Pablo
Summary: This study describes the challenges in observing the variable photometric properties of the binary system WR48 in the Theta Mus = HD 113904 system due to the interference from the highly luminous blue supergiant BSG. Despite extensive optical space-based photometry, the intrinsic stochastic variability from the BSG continues to hinder the detection of atmospheric eclipse in the system. By adopting a more reliable orbital inclination, researchers were able to obtain an upper limit for the mass-loss rate of the WR component and the depth of the atmospheric eclipse in the WR48 subsystem.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
G. Lenoir-Craig, I. I. Antokhin, E. A. Antokhina, N. St-Louis, A. F. J. Moffat
Summary: WR22 = HD 92740 is a bright double-line WN7h + O9III-V binary system, exhibiting a deep eclipse phenomenon during periastron passage. Models L96 and A13 are applied to analyze the optical observations, providing insights into the physical characteristics of the stars in the binary system.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
Rodolfo H. Barba, Roberto C. Gamen, Pablo Martin-Ravelo, Julia Arias, Nidia Morrell
Summary: WR 21a is a spectroscopic binary with massive stars. Photometric variations and tidally excited oscillations have been discovered. The orbital solution and mass estimates have been determined through modeling and measurements.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)
Article
Astronomy & Astrophysics
A. Sixtos, A. Wofford, A. A. C. Sander, A. Peimbert
Summary: Observing the emission lines of star-forming galaxies can help understand the sources of He+-ionizing photons. In metal-poor starburst galaxies, the broad underlying component of nebular He II lambda 4686 is believed to come from the winds of classical Wolf-Rayet stars, specifically the WN subtype. However, our observations of HD 5980 suggest that the broad He II emission is likely contamination from the multiple-star system rather than from the WN stars. Modelling shows that the O stars in coeval stellar populations can be the main emitters of He+-ionizing radiation.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
I Shaposhnikov, A. Cherepashchuk, A. Dodin, K. Postnov
Summary: This article presents the results of new photometric and spectroscopic observations of the WN5 + O6 binary V444 Cyg and provides a detailed analysis of existing spectroscopy and photometry. The study determined the masses and orbit sizes of the components of V444 Cyg, as well as estimated the secular increase rate of the orbital period and the stellar wind mass-loss rate from the WR star.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
J. S. Clark, M. E. Lohr, F. Najarro, L. R. Patrick, B. W. Ritchie
Summary: Serving as progenitors for different transient phenomena, massive stars have received increasing attention in recent years. However, many aspects of their birth and evolution, especially in binary interactions, are still unclear. Our study focuses on the binary properties of the Arches cluster, which is home to numerous massive stars. Observations of the cluster members reveal a lower limit of about 43% binary fraction, increasing to around 50% for certain types of massive stars. Analysis of the data suggests the formation and evolution of these binaries through a single-star channel, although a binary formation channel cannot be excluded for some systems. A qualitative comparison with lower mass OB-type stars indicates a trend of extreme binary fraction extending to the most massive stars currently forming in the local Universe.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
J. W. Eatson, J. M. Pittard, S. Van Loo
Summary: Dust production is a curious phenomenon in massive binary systems, and factors such as higher mass-loss rates, close orbits, and high-velocity wind shear contribute to higher dust yields.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2022)