Three new identifications of extended UV emission around AGB stars

Author(s)

Guerrero, M. A. ; Ortiz, R.

• Document type: Journal article
• Source: Monthly Notices of the Royal Astronomical Society; v. 527, n. 3, p. 9-pg., 2023-11-28.

Abstract

Asymptotic giant branch (AGB) stars experience heavy episodes of mass-loss through a slow stellar wind during the thermal pulse phase that form large, pc-scale structures around them. As the AGB stellar wind interacts with the interstellar medium (ISM), the otherwise isotropic ejecta gets distorted, resulting in asymmetric shapes, bow-shock structures and, in the case of fast motion relative to the surrounding ISM, extended w ak es and tails as unexpectedly detected in GALEX ultraviolet (UV) images of o Cet, also known as Mira. Since that disco v ery, another fourteen AGB stars have been reported to exhibit extended UV emission around them. Here, we present the disco v ery of extended UV emission around another three AGB stars, namely R For, R Hor, and DM Tuc. The analysis of the o v erall properties of the re gions of e xtended UV emission indicates that these are preferentially detected in closer AGB stars far away from the Galactic plane, i.e. sources less e xtincted. F aster AGB stars tend to have more elongated shapes, with bow-shocks and w ak es or tails of material, while AGB stars f arther aw ay from the Galactic plane tend to be surrounded by larger regions of UV emission. (AU)

• FAPESP's process: 23/05298-0 - Circumstellar shells around AGB stars
• Grantee: Roberto Pereira Ortiz
• Support Opportunities: Regular Research Grants