2019ApJ...886..121B -
Astrophys. J., 886, 121-121 (2019/December-1)
A new formation model for ω Centauri: a complex interplay of astrophysical processes.
BEKKI K. and TSUJIMOTO T.
Abstract (from CDS):
We investigate the formation processes of the Galactic globular cluster (GC) ω Cen with multiple stellar populations based on our original hydrodynamical simulations with chemical enrichment by Type II supernovae (SNe II), asymptotic giant branch (AGB) stars, and neutron star mergers (NSMs). Multiple stellar populations with a wide range of [Fe/H] can be formed from rather massive and compact molecular clouds with a mass of ≃2 x 107 M☉ in the central region of its dwarf galaxy within less than a few hundred megayears. Gas ejected from SNe II and AGB stars can mix well to form new stars with higher He abundances (Y) and higher [Fe/H]. The He-rich stars are strongly concentrated in the GC's central region so that the GC can show a steep negative gradient of Y. Relative ratios of light elements to Fe show bimodal distributions for a given [Fe/H] owing to star formation from original gas and AGB ejecta. [La/Fe] and [Ba/Fe] can rapidly increase until [Fe/H] ∼ -1.5 and then decrease owing to Fe ejection from SNe II. Although AGB ejecta can be almost fully retained in the intracluster medium, NSM ejecta can be retained only partially. This difference in the retention capability is responsible for the observed unique [Eu/Fe]-[Fe/H] and [La/Eu]-[Fe/H] relations in ω Cen. The observed [O/Na]-[Fe/H] relation and radial [Fe/H] gradient are yet to be well reproduced in the present model. We briefly discuss how the results change for different yields of AGB stars and SNe II.
Abstract Copyright:
© 2019. The American Astronomical Society. All rights reserved.
Journal keyword(s):
Globular star clusters - Chemical abundances - Galaxy abundances - Asymptotic giant branch - Neutron stars
Simbad objects:
3
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2019ApJ...886..121B and select 'bookmark this link' or equivalent in the popup menu