EDP Sciences

Vol. 540
In section 7. Stellar structure and evolution

Infrared excess around nearby red giant branch stars and Reimers law

by M. A. T. Groenewegen, A&A 540, A32

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While the winds of stars on the asymptotic giant branch have been subject to many investigations, stars on the first red giant branch have attracted much less attention. This article investigates the mass loss rates of stars on the first red giant branch. Stars with good Hipparcos parallaxes were selected, and mass loss estimated from modeling the infrared flux distribution. A Reimers style mass loss law was fitted to the data and compared to recent results for globular clusters. A perplexing result is that about 50% of the red giants show measurable mass loss, while other stars with similar parameters do not. A possible explanation could be episodic mass-loss events.