Extended far-UV emission surrounding AGB stars as seen by GALEX

Autor(en)

Vlad Rastau, Marko Mecina, Franz Kerschbaum, Hans Olofsson, Matthias Maercker, Marcel Drechsler, X. Strottner, L. Mulato

Abstrakt

The asymptotic giant branch (AGB) is the final stage in the evolution of low-to-intermediate mass stars, before they become white dwarfs. Experiencing strong convective dredge-up and slow pronounced dusty winds, AGB stars contribute a significant amount to the enrichment of the interstellar medium. The mass-loss process involved in this evolutionary stage (caused in part by the dusty winds) is responsible for the formation of large dust and gas structures around such stars. So far, extended emission originating from such structures has mainly been observed in the infrared regime. However, recently more examples of emission associated with large scale features around AGB stars have been reported in the UV regime (Mira by Martin et al. 2007, CW Leo and RW LMi by Sahai & Chronopoulos 2010 and Sahai & Mack-Crane 2014, respectively). This poster showcases the results based on a recent systematic Aladin survey of extended UV or IR emission structures associated with evolved AGB variables. The sample covers several, so far unknown, extended features in GALEX FUV (far-UV 0.13 - 0.18 micron), ranging from very faint and barely visible ones to large, pronounced rings or bubbles. For most of the objects the FUV emission has an infrared counterpart. High quality UV observations of AGB stars and their surroundings are currently few in number, so valuable information with respect to stellar evolution could be gained

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Chalmers University of Technology, Sternwarte Bärenstein, Èquipe StDr, Southern Spectroscopic Observing Team

Publikationsdatum

2023

ÖFOS 2012

103003 Astronomie

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/cff8e5ae-1b4d-4ed0-bf54-bca29f6dcd4d