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arXiv · 2507.13151

Infrared Spectroscopy of V838 Monocerotis in 2015 and 2022

T. R. Geballe·B. M. Kaminskiy·D. P. K. Banerjee·A. Evans·Y. Pavlenko·M. T. Rushton·M. Popescu·S. P. S. Eyres
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Abstract

We report medium-resolution $0.85-2.45\,\mu$m spectroscopy obtained in 2015 and 2022 and high resolution $2.27-2.39\,\mu$m and $4.59-4.77\,\mu$m spectroscopy obtained in 2015 of V838 Monocerotis, along with modeling of the $0.85-2.45\,\mu$ spectrum. V838 Mon underwent a series of eruptions and extreme brightenings in 2002, which are thought to have occured 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 200kms$^{-1}$.

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T. R. Geballe, B. M. Kaminskiy, D. P. K. Banerjee, A. Evans, Y. Pavlenko, M. T. Rushton, M. Popescu, S. P. S. Eyres. 2025-07-17. Infrared Spectroscopy of V838 Monocerotis in 2015 and 2022. https://arxiv.org/abs/2507.13151

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