2009/03/17 by Sukyoung K. Yi, Yi, Sukyoung K.
Physics and Astronomy · #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Quantum, superfluid, helium dynamics #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.48550/arxiv.0903.2891
10 pages, Review at the IAUS258 (The Ages of Stars) in Baltimore
arxiv created 2009/03/17 · openalex publication_date 2009/03/17 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The spreads in chemical abundances inferred by recent precision observations suggest that some or possibly all globular clusters can no longer be considered as simple stellar populations. The most striking case is omega Cen in the sense that its bluest main-sequence despite its high metallicity demands an extreme helium abundance of Y > 0.4. I focus on this issue of "the extreme helium population problem" in this review.