2016/08/30 by Jae-Woo Lee · 27 citations
Physics and Astronomy · #Abundance (ecology) #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Biology #Cluster (spacecraft) #Dwarf galaxy #Ecology #Galaxy #Globular cluster #Metallicity #Physics #Red-giant branch #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR
paper · pdf · doi:10.3847/0067-0049/226/2/16
published in The Astrophysical Journal Supplement Series 226(2), 16 (Institute of Physics) · Accepted for publication in ApJS
arxiv created 2016/08/30 · openalex publication_date 2016/10/01 · arxiv updated 2016/10/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT In our previous study, we showed that the peculiar globular cluster (GC) M22 contains two distinct stellar populations, namely the Ca - w and Ca - s groups, which have different physical properties, chemical compositions, spatial distributions, and kinematics. We proposed that M22 was most likely formed via a merger of two GCs with heterogeneous metallicities in a dwarf galaxy environment and then later accreted to our Galaxy. In their recent study, Mucciarelli et al. claimed that M22 is a normal monometallic globular cluster without any perceptible metallicity spread among the two groups of stars, which challenges our results and those of others. We devise new strategies for the local thermodynamic equilibrium abundance analysis of red giant branch stars in GCs and show that there exists a spread in the iron abundance distribution in M22.