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arXiv · 2407.20602

A radio loud semiregular variable

Pedro L. Luque-Escamilla·Josep Martí
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Abstract

As a byproduct of our search for Galactic stellar systems with gamma-ray emission, we have identified an unrelated cool and evolved star (IRC-10412) that attracted our attention due to its strong radio emission level with a spectral index matching, almost perfectly, the canonical +0.6 value expected from an ionized stellar wind. A follow-up observational analysis was undertaken given that these two properties are hard to reconcile as originating in the same stellar object. As a result, IRC-10412 has been classified as a new semiregular variable of SRb type in the asymptotic giant branch, and different but consistent estimates of its mass-loss parameter are reported. We propose that its unusually high radio emission arises from a ~ 1E-5 Msun/yr stellar wind exposed to an external source of ionizing photons, possibly coming from nearby OB associations.

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Pedro L. Luque-Escamilla, Josep Martí. 2024-07-30. A radio loud semiregular variable. https://arxiv.org/abs/2407.20602

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