Reduction of the maximum mass-loss rate of OH/IR stars due to unnoticed binary interaction
Introductory text in journal, 2019

© 2019, The Author(s), under exclusive licence to Springer Nature Limited. In 1981, the idea of a superwind that ends the life of cool giant stars was proposed 1 . Extreme oxygen-rich giants, OH/IR stars, develop superwinds with the highest mass-loss rates known so far, up to a few 10 −4 solar masses (M ⊙ ) per year 2–12 , informing our understanding of the maximum mass-loss rate achieved during the asymptotic giant branch (AGB) phase. A conundrum arises whereby the observationally determined duration of the superwind phase is too short for these stars to lose enough mass to become white dwarfs 2–4,6,8–10 . Here we report on the detection of spiral structures around two cornerstone extreme OH/IR stars, OH 26.5 + 0.6 and OH 30.1 − 0.7, thereby identifying them as wide binary systems. Hydrodynamic simulations show that the companion’s gravitational attraction creates an equatorial density enhancement mimicking a short, extreme superwind phase, thereby solving the decades-old conundrum. This discovery restricts the maximum mass-loss rate of AGB stars to around the single-scattering radiation pressure limit of a few 10 −5 M ⊙ yr −1 . This has crucial implications for nucleosynthetic yields, planet survival and the wind-driving mechanism.

Author

L. Decin

University of Leeds

KU Leuven

W. Homan

KU Leuven

Taissa Danilovich

KU Leuven

A. de Koter

Anton Pannekoek Institute for Astronomy

KU Leuven

D. Engels

Universität Hamburg

Lbfm Waters

Netherlands Institute for Space Research (SRON)

Anton Pannekoek Institute for Astronomy

Sebastien Muller

Chalmers, Space, Earth and Environment, Onsala Space Observatory, Onsala Space Observatory, Observation Support

C. Gielen

KU Leuven

D. A. García-Hernández

University of La Laguna

Instituto Astrofisico de Canarias

R. J. Stancliffe

University of Hull

University of Birmingham

M. Van De Sande

KU Leuven

G. Molenberghs

KU Leuven

Universiteit Hasselt

F. Kerschbaum

University of Vienna

A. Zijlstra

The University of Hong Kong

University of Manchester

I. El Mellah

KU Leuven

Nature Astronomy

23973366 (eISSN)

Subject Categories

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

Metallurgy and Metallic Materials

Infrastructure

Onsala Space Observatory

DOI

10.1038/s41550-019-0703-5

More information

Latest update

2/12/2020