Primordial pollution of globular clusters within their host dwarfs embedded in dark matter halos at high redshifts

Abstract

Recent observational studies have revealed star-to-star abundance inhomogeneity among light elements (e.g., C, N, O, Na, and Al) of stars on the main sequence in the Galactic globular clusters (GCs). One of promising interpretations for this result is that the observed abundance inhomogeneity is due to the second generation of stars formed from ejecta of the first generation of evolved stars (e.g., AGB stars) within GCs. However it remains unclear whether and how this primordial pollution can occur within GCs. We here propose a new scenario in which primordial pollution of GCs is highly likely to occur if GCs are located in the central regions of high redshift dark matter subhalos that can host low-mass dwarf galaxies. In this scenario, gas ejected from the first generation of stars of GCs can be effectively trapped in the deep gravitational potential of their host halos and consequently can be consumed for the formation of the second generation of stars without losing a significant amount of gas by ram pressure stripping of interstellar and intergalactic medium. During merging of these halos with the proto-Galaxy, the halos are completely destroyed owing to the strong tidal field of the Galaxy. The self-polluted GCs located initially in the central regions of the halos can survive from tidal destruction owing to their compactness and finally become the Galactic halo GCs. In this scenario, ejecta of field stars surrounding the central GCs can be also converted into stars within their host dwarfs and finally become the second generation of stars of GCs. We also discuss the origin of the difference in the degree of abundance inhomogeneity between different GCs, such as $\omega$ Centauri and NGC 6752, in terms of the difference in physical properties between host halos from which GC originate.

5 pages, 2 figures, accepted by MNRAS Letters

References in corpus (5)

• Stellar Chemical Signatures And Hierarchical Galaxy Formation
• Globular Clusters with Dark Matter Halos. II. Evolution in Tidal Field
• Formation of intracluster globular clusters
• The Galactic globular cluster system as a fossil record of reionization
• Self-enrichment in globular clusters. I. An analytic approach

Cited by in corpus (20)

• Na-O Anticorrelation and HB. VIII. Proton-capture elements and metallicities in 17 globular clusters from UVES spectra
• Globular clusters as the relics of regular star formation in 'normal' high-redshift galaxies
• An abundance analysis of bright giants in the globular cluster NGC 1851
• Globular cluster formation in the context of galaxy formation and evolution
• Secondary star formation within massive star clusters: Origin of multiple stellar populations in globular clusters
• Origin of Abundance Inhomogeneity in Globular Clusters
• Space Velocities of Southern Globular Clusters. V. A Low Galactic Latitude Sample
• Rotation and multiple stellar population in globular clusters
• On The Birth Masses of the Ancient Globular Clusters
• A spectral atlas of post-main-sequence stars in omega Centauri: kinematics, evolution, enrichment and interstellar medium
• The origin of discrete multiple stellar populations in globular clusters
• Evidence for metallicity spreads in three massive M31 globular clusters
• Massive stars and globular cluster formation
• Formation of globular clusters with multiple stellar populations from massive gas clumps in high-z gas-rich dwarf galaxies
• An AKARI Search for Intracluster Dust of Globular Clusters
• Star formation within globular clusters:discrete multiple bursts and top-light mass functions
• The Celestial Buffet: multiple populations and globular cluster formation in dwarf galaxies
• Formation of the Galactic globular clusters with He-rich stars in low-mass halos virialized at high redshift
• A new formation model for omega Centauri: the crossroad of astrophysical processes
• Different Sodium enhancements among multiple populations of Milky Way globular clusters