The Chemical Evolution of Heavy Elements in Globular Clusters

Shingles, Luke J.; Karakas, Amanda I.; Hirschi, Raphael

Abstract

We present preliminary results from a chemical evolution model that tracks the composition of heavy elements beyond iron in a globular cluster. The heavy elements can be used as tracers of the nucleosynthetic events that defined the formation and evolution of star clusters in the early Universe. In particular, the chemical evolution model focuses on the hypothesis that rapidly-rotating massive stars produced the heavy elements via the slow neutron-capture process and seeded the proto-cluster while the stars we see today were still forming.

We compare our model with heavy element abundances in M4 and M5, and M22. Our results are strongly dependent on the highly uncertain rate of the 17O(α,γ)21Ne reaction, which determines the strength of 16O as a neutron poison. We find that the [Pb/Ba] ratio is too low to match the empirical value, which might suggest that a contribution from AGB stars is required.

Citation

Shingles, L. J., Karakas, A. I., & Hirschi, R. (2013). The Chemical Evolution of Heavy Elements in Globular Clusters. . https://doi.org/10.1017/s1743921313007059

• Conference Name: Symposium S298: Setting the scene for Gaia and LAMOST
• Online Publication Date: Jan 6, 2014
• Publication Date: 2013-05
• Deposit Date: Jun 16, 2023
• Publisher: Cambridge University Press
• Volume: 9
• Pages: 439-440
• Series Title: Proceedings of the International Astronomical Union
• DOI: https://doi.org/10.1017/s1743921313007059
• Keywords: Astronomy and Astrophysics; Space and Planetary Science