Thermohaline mixing and the variation of [C/Fe] with magnitude in M3

Summary, in English

We use observations of M3 to constrain thermohaline mixing. This is done by matching [C/Fe] and [N/Fe] along the RGB of M3. We find our models can explain observations if it is assumed there is a spread of ∼ 0.3 - 0.4 dex in [C/Fe] in the stars in M3 from their birth. We reproduce the full spread in [C/Fe] at the tip of the RGB. Thermohaline mixing can produce a significant change in [N/Fe] as a function of absolute magnitude on the RGB for initially CN-weak stars, but not for initially CN-strong stars, which have so much nitrogen to begin with that any deep mixing does not significantly affect the surface nitrogen composition.

• Author: George C. Angelou; John C. Lattanzio; Ross P. Church; Richard J. Stancliffe; David S. Dearborn; Graeme H. Smith; Christopher A. Tout; Verne V. Smith
• Department/s: Lund Observatory - Has been reorganised
• Publishing year: 2010-12-01
• Language: English
• Publication/Series: Proceedings of Science
• Document type: Conference paper
• Topic: Astronomy, Astrophysics and Cosmology
• Conference name: 11th Symposium on Nuclei in the Cosmos, NIC 2010
• Conference date: 2010-07-19 - 2010-07-23
• Conference place: Heidelberg, Germany
• Status: Published