A General Abundance Problem for All Self-Enrichment Scenarios for the Origin of Multiple Populations in Globular Clusters

Abstract

A number of stellar sources have been advocated as the origin of the enriched material required to explain the abundance anomalies seen in ancient globular clusters (GCs). Most studies to date have compared the yields from potential sources (asymptotic giant branch stars (AGBs), fast rotating massive stars (FRMS), high mass interacting binaries (IBs), and very massive stars (VMS)) with observations of specific elements that are observed to vary from star-to-star in GCs, focussing on extreme GCs such as NGC 2808, which display large He variations. However, a consistency check between the results of fitting extreme cases with the requirements of more typical clusters, has rarely been done. Such a check is particularly timely given the constraints on He abundances in GCs now available. Here we show that all of the popular enrichment sources fail to reproduce the observed trends in GCs, focussing primarily on Na, O and He. In particular, we show that any model that can fit clusters like NGC 2808, will necessarily fail (by construction) to fit more typical clusters like 47 Tuc or NGC 288. All sources severely over-produce He for most clusters. Additionally, given the large differences in He spreads between clusters, but similar spreads observed in Na--O, only sources with large degrees of stochasticity in the resulting yields will be able to fit the observations. We conclude that no enrichment source put forward so far (AGBs, FRMS, IBs, VMS - or combinations thereof) is consistent with the observations of GCs. Finally, the observed trends of increasing [N/Fe] and He spread with increasing cluster mass cannot be resolved within a self-enrichment framework, without further exacerbating the mass budget problem.

15 pages, 9 figures, accepted to MNRAS

References in corpus (13)

• Formation and Dynamical Evolution of Multiple Stellar Generations in Globular Clusters
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. I. Overview of the Project and Detection of Multiple Stellar Populations
• Spectroscopic and Photometric evidence of two stellar populations in the Galactic Globular Cluster NGC6121 (M4)
• Origin of the abundance patterns in Galactic globular clusters: constraints on dynamical and chemical properties of globular clusters
• Studying the YMC population of M83: how long clusters remain embedded, their interaction with the ISM and implications for GC formation theories
• Helium and Multiple Populations in the Massive Globular Cluster NGC6266 (M62)
• The primordial and evolutionary abundance variations in globular-cluster stars: a problem with two unknowns
• Constraining globular cluster formation through studies of young massive clusters - V. ALMA observations of clusters in the Antennae
• Constraining Globular Cluster Formation Through Studies of Young Massive Clusters - IV. Testing the Fast Rotating Massive Star Scenario
• Radial distributions of sub-populations in the globular cluster M15: a more centrally concentrated primordial population
• Constraining globular cluster formation through studies of young massive clusters - III. A lack of gas and dust in massive stellar clusters in the LMC and SMC
• Three discrete groups with homogeneous chemistry along the red giant branch in the globular cluster NGC 2808
• Heart of Darkness: dust obscuration of the central stellar component in globular clusters younger than ~100Myr in multiple stellar population models

Cited by in corpus (1)

• Dynamical Constraints on the Origin of Multiple Stellar Populations in Globular Clusters