Infrared spectroscopy of V838 Monocerotis in 2015 and 2022

Geballe, T R; Kaminskiy, B M; Banerjee, D P K; Evans, A; Pavlenko, Y; Rushton, M T; Popescu, M; Eyres, S P S

Abstract

We report medium-resolution 0.85–2.45 m spectroscopy obtained in 2015 and 2022 and high-resolution 2.27–2.39 m and 4.59–4.77 m spectroscopy obtained in 2015 of V838 Monocerotis (V838 Mon), along with modelling of the 0.85–2.45 m spectrum. V838 Mon underwent a series of eruptions and extreme brightenings in 2002, which are thought to have occurred as a result of a stellar merger. The new spectra and modelling of them reveal a disturbed red giant photosphere that is probably continuing to contract and ejecta that are cooling and continuing to disperse at velocities up to 200 km s−1.

Citation

Geballe, T. R., Kaminskiy, B. M., Banerjee, D. P. K., Evans, A., Pavlenko, Y., Rushton, M. T., Popescu, M., & Eyres, S. P. S. (2025). Infrared spectroscopy of V838 Monocerotis in 2015 and 2022. Monthly Notices of the Royal Astronomical Society, 541(4), 3331-3340. https://doi.org/10.1093/mnras/staf1193

• Journal Article Type: Article
• Acceptance Date: Jul 15, 2025
• Online Publication Date: Jul 21, 2025
• Publication Date: 2025-08
• Deposit Date: Aug 4, 2025
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 541
• Issue: 4
• Pages: 3331-3340
• DOI: https://doi.org/10.1093/mnras/staf1193
• Keywords: stars: individual: V838 Monocerotis, stars: late-type, line: identification, line: profiles
• Public URL: https://keele-repository.worktribe.com/output/1362729
• Publisher URL: https://academic.oup.com/mnras/article/541/4/3331/8209895