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arXiv · 2604.11907

Intermediate-Mass Mergers: A New Scenario for Several FS CMa Stars

Daniela Korcakova·Nela Dvorakova·Iris Bermejo Lozano·Gregg A. Wade·Alicia Moranchel Basurto·Pavel Kroupa·Raul Ortega Chametla·Colin Peter Folsom·Ondrej Juhas
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Abstract

We summarise the properties and nature of a peculiar group of B-type stars called FS CMa stars. These stars show the B[e] phenomenon, i.e., their spectra exhibit both forbidden emission lines and infrared excess. Such properties point to an extended circumstellar gas and dust component. Although the phenomenon has been explained in most B[e] stars, the origin and nature of FS CMa stars is disputed. Here, we focus on the merger hypothesis, for which evidence has recently been discovered.

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Daniela Korcakova, Nela Dvorakova, Iris Bermejo Lozano, Gregg A. Wade, Alicia Moranchel Basurto, Pavel Kroupa, Raul Ortega Chametla, Colin Peter Folsom, Ondrej Juhas. 2026-04-13. Intermediate-Mass Mergers: A New Scenario for Several FS CMa Stars. https://doi.org/10.3390/galaxies13030046

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