The Colliding-wind Binary HD 168112
email : Ronny.Blomme@oma.be
Faculté des Sciences de la Motricité, Université Libre de Bruxelles, Anderlecht, Belgium
Universidad de La Laguna, Departamento de Astrofísica, La Laguna, Tenerife, Spain
Résumé
HD 168112 est un émetteur radio non thermique qui n’a été que récemment confirmé comme binaire spectroscopique par Putkuri et al. (2023, DOI : 10.1093/mnras/stad2657). Nous utilisons des observations spectroscopiques indépendantes pour déterminer les paramètres orbitaux. Nous analysons également les observations radio que nous avons recueillies lors de son passage au périastre. Alors que les autres phases orbitales montrent clairement une émission non thermique, les phases proches du périastre sont thermiques et sont dominées par le bremsstrahlung dans la région de la collision des vents.
Abstract
HD 168112 is a non-thermal radio emitter that has only recently been confirmed as a spectroscopic binary by Putkuri et al. (2023, DOI: 10.1093/mnras/stad2657). We use an independent set of spectroscopic observations to determine its orbital parameters. We also analyse radio observations we collected around its periastron passage. While other orbital phases clearly show non-thermal emission, the phases near periastron are thermal and are dominated by the free–free emission in the colliding-wind region.
This work is distributed under the Creative Commons CC BY 4.0 Licence.
Paper presented at the 41st Liège International Astrophysical Colloquium on “The eventful life of massive star multiples,” University of Liège (Belgium), 15–19 July 2024.
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