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Title: (Sub)stellar companions shape the winds of evolved stars

Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.

Authors:
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Publication Date:
NSF-PAR ID:
10192925
Journal Name:
Science
Volume:
369
Issue:
6510
Page Range or eLocation-ID:
p. 1497-1500
ISSN:
0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)
Sponsoring Org:
National Science Foundation
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