HEAVY-ELEMENT DISPERSION IN THE METAL-POOR GLOBULAR CLUSTER M92

2011/04/30 by Ian U. Roederer, Christopher Sneden, C. Sneden · 65 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Dispersion (optics) #Globular cluster #Materials science #Metal #Metallicity #Nucleosynthesis #Observatory #Optics #Physics #Spectral line #Spectrograph #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.SR

paper · pdf · doi:10.1088/0004-6256/142/1/22

published in The Astronomical Journal 142(1), 22 (Institute of Physics) · Accepted for publication in the Astronomical Journal (22 pages, 12 figures). v2: references updated

arxiv created 2011/05/10 · openalex publication_date 2011/06/09 · arxiv updated 2015/05/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Dispersion among the light elements is common in globular clusters (GCs), while dispersion among heavier elements is less common. We present detection of r-process dispersion relative to Fe in 19 red giants of the metal-poor GC M92. Using spectra obtained with the Hydra multi-object spectrograph on the WIYN Telescope at Kitt Peak National Observatory, we derive differential abundances for 21 species of 19 elements. The Fe-group elements, plus Y and Zr, are homogeneous at a level of 0.07-0.16 dex. The heavy-elements La, Eu, and Ho exhibit clear star-to-star dispersion spanning 0.5-0.8 dex. The abundances of these elements are correlated with one another, and we demonstrate that they were produced by r-process nucleosynthesis. This r-process dispersion is not correlated with the dispersion in C, N, or Na in M92, indicating that r-process inhomogeneities were present in the gas throughout star formation. The r-process dispersion is similar to that previously observed in the metal-poor GC M15, but its origin in M15 or M92 is unknown at present.

Citations

• Blue Horizontal Branch Stars in M92
• A LARGE C+N+O ABUNDANCE SPREAD IN GIANT STARS OF THE GLOBULAR CLUSTER NGC 1851
• Abundances In Very Metal‐Poor Dwarf Stars
• MASS OUTFLOW AND CHROMOSPHERIC ACTIVITY OF RED GIANT STARS IN GLOBULAR CLUSTERS. II. M13 AND M92
• PRODUCTION OF LIGHT-ELEMENT PRIMARY PROCESS NUCLEI IN NEUTRINO-DRIVEN WINDS
• Heavy Element Abundances in Giant Stars of the Globular Clusters M4 and M5
• A Catalog of Parameters for Globular Clusters in the Milky Way
• IMPROVED LABORATORY TRANSITION PROBABILITIES FOR Ce II, APPLICATION TO THE CERIUM ABUNDANCES OF THE SUN AND FIVE r- PROCESS-RICH, METAL-POOR STARS, AND RARE EARTH LAB DATA SUMMARY
• THE END OF NUCLEOSYNTHESIS: PRODUCTION OF LEAD AND THORIUM IN THE EARLY GALAXY
• Neutron-Capture Elements in the Early Galaxy
• First stars XII. Abundances in extremely metal-poor turnoff stars, and comparison with the giants
• Improved Laboratory Transition Probabilities for Eriiand Application to the Erbium Abundances of the Sun and Fiver‐Process‐rich, Metal‐poor Stars
• The Two Micron All Sky Survey (2MASS)
• The Chemical Composition of the Sun

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• Principal component analysis on chemical abundances spaces
• The most metal-poor Galactic globular cluster: the first spectroscopic observations of ESO280-SC06
• A photometric study of globular clusters observed by the APOGEE survey