Visual Orbits of Wolf–Rayet Stars. II. The Orbit of the Nitrogen-rich Wolf–Rayet Binary WR 138 Measured with the CHARA Array
Abstract Classical Wolf–Rayet (WR) stars are descendants of massive OB-type stars that have lost their hydrogen-rich envelopes and are in the final stages of stellar evolution, possibly exploding as Type Ib/c supernovae. It is understood that the mechanisms driving this mass loss are either strong stellar winds and or binary interactions, so intense studies of these binaries including their evolution can tell us about the importance of the two pathways in WR formation. WR 138 (HD 193077) has a period of just over 4 yr and was previously reported to be resolved through interferometry. We report on new interferometric data combined with spectroscopic radial velocities in order to provide a three-dimensional orbit of the system. The precision on our parameters tend to be about an order of magnitude better than previous spectroscopic techniques. These measurements provide masses of the stars, namely, M WR = 13.93 ± 1.49 M ⊙ and M O = 26.28 ± 1.71 M ⊙ . The derived orbital parallax agrees with the parallax from Gaia, namely, with a distance of 2.13 kpc. We compare the system’s orbit to models from BPASS, showing that the system likely may have been formed with little interaction but could have formed through some binary interactions either following or at the start of a red supergiant phase but with the most likely scenario occurring as the red supergiant phase starts for a ∼40 M ⊙ star.
Authors
- Cyprien Lanthermann (ORCID: https://orcid.org/0000-0001-9745-5834)
- Gail H. Schaefer (ORCID: https://orcid.org/0000-0001-5415-9189)
- Sorabh Chhabra
- Mayra Gutierrez (ORCID: https://orcid.org/0009-0006-0225-4444)
- John D. Monnier (ORCID: https://orcid.org/0000-0002-3380-3307)
- Benjamin R. Setterholm (ORCID: https://orcid.org/0000-0001-5980-0246)
- Jonathan Mackey (ORCID: https://orcid.org/0000-0002-5449-6131)
- A. F. J. Moffat (ORCID: https://orcid.org/0000-0002-4333-9755)
- Stefan Kraus (ORCID: https://orcid.org/0000-0001-6017-8773)
- Narsireddy Anugu (ORCID: https://orcid.org/0000-0002-2208-6541)
- Grant M. Hill (ORCID: https://orcid.org/0000-0002-7648-9119)
- Aaron Labdon (ORCID: https://orcid.org/0000-0001-8837-7045)
- Jacob Ennis (ORCID: https://orcid.org/0000-0002-1575-4310)
- Noel D. Richardson (ORCID: https://orcid.org/0000-0002-2806-9339)
- Tyler Gardner (ORCID: https://orcid.org/0000-0002-3003-3183)
- Noura Ibrahim (ORCID: https://orcid.org/0000-0002-1788-9366)
- Felipe Navarete (ORCID: https://orcid.org/0000-0002-0284-0578)
- J. J. Eldridge (ORCID: https://orcid.org/0000-0002-1722-6343)
- Isabelle Codron (ORCID: https://orcid.org/0009-0005-8088-0718)
- Jean-Baptiste Le Bouquin
- Becca Spejcher (ORCID: https://orcid.org/0009-0003-7036-2840)
Institutions
- Dublin Institute For Advanced Studies (IE)
- University of Auckland (NZ)
- University of Exeter (GB)
- University of Michigan (US)
- W.M. Keck Observatory (US)
- Max Planck Institute for Astronomy (DE)
- Institut de Planétologie et d'Astrophysique de Grenoble (FR)
- Southern Astrophysical Research Telescope (CL)
- European Southern Observatory (CL)
- Mount Wilson Observatory (US)
- Université de Montréal (CA)
- Embry–Riddle Aeronautical University (US)
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2024-12-01
- DOI
- https://doi.org/10.3847/1538-4357/ad9024
- Citations
- 3
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.99
Funders
- National Science Foundation
- National Aeronautics and Space Administration
- W. M. Keck Foundation
- Research Corporation for Science Advancement
- Arizona Space Grant Consortium
- California Institute of Technology
- Embry-Riddle Aeronautical University
- Georgia State University
- European Commission
- Science Foundation Ireland
- Office of the Vice President for Research and Economic Development, University at Buffalo
- HORIZON EUROPE European Research Council