Heavy Element Dispersion in the Metal-Poor Globular Cluster M92

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.

Accepted for publication in the Astronomical Journal (22 pages, 12 figures). v2: references updated

References in corpus (17)

• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• The Abundances of Neutron Capture Species in the Very Metal-Poor Globular Cluster M15: An Uniform Analysis of RGB and RHB Stars
• Near-UV Observations of HD221170: New Insights into the Nature of r-Process-Rich Stars
• Production of Light Element Primary Process nuclei in neutrino-driven winds
• New Rare Earth Element Abundance Distributions for the Sun and Five r-Process-Rich Very Metal-Poor Stars
• The two metallicity groups of the globular cluster M22: a chemical perspective
• Improved Laboratory Transition Probabilities for Neutral Chromium and Re-determination of the Chromium Abundance for the Sun and Three Stars
• An abundance analysis of bright giants in the globular cluster NGC 1851
• 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
• A large C+N+O abundance spread in giant stars of the globular cluster NGC 1851
• Improved Laboratory Transition Probabilities for Er II and Applications to the Erbium Abundances of the Sun and Five r-Process Rich, Metal-Poor Stars
• Heavy element abundances in giant stars of the globular clusters M4 and M5
• Primordial r-process Dispersion in Metal-Poor Globular Clusters
• Rubidium and lead abundances in giant stars of the globular clusters M4 and M5
• Neutron-capture elements in the metal-poor globular cluster M15
• Mass Outflow and Chromospheric Activity of Red Giant Stars in Globular Clusters II. M13 and M92
• The Global Kinematics of the Globular Cluster M92

Cited by in corpus (49)

• Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• Synthetic Stellar Photometry - I. General considerations and new transformations for broad-band systems
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code. II. The Southern Clusters and Overview
• Exploring Anticorrelations and Light Element Variations in Northern Globular Clusters Observed by the APOGEE Survey
• Calibrations of Atmospheric Parameters Obtained from the First Year of SDSS-III APOGEE Observations
• Metal Abundances, Radial Velocities and other Physical Characteristics for the RR Lyrae Stars in the Kepler Field
• An Application of Deep Neural Networks in the Analysis of Stellar Spectra
• Stroemgren survey for Asteroseismology and Galactic Archaeology: let the SAGA begin
• Nearest Neighbor: The Low-Mass Milky Way Satellite Tucana III
• Isochrones for Old (> 5 Gyr) Stars and Stellar Populations. I. Models for $-2.4\le$ [Fe/H] $\le +0.6$, $0.25\le Y\le 0.33$, and $-0.4\le$ [$\alpha$\Fe] $\le +0.4$
• A homogeneous analysis of globular clusters from the APOGEE survey with the BACCHUS code. I. The Northern clusters
• Principal Component Analysis on Chemical Abundances Spaces
• Fourier analysis of non-Blazhko ab-type RR Lyrae stars observed with the Kepler space telescope
• Three Ancient Halo Subgiants: Precise Parallaxes, Compositions, Ages, and Implications for Globular Clusters
• The Role of Thermohaline Mixing in Intermediate- and Low-Metallicity Globular Clusters
• Characterizing the Heavy Elements in Globular Cluster M22 and an Empirical s-process Abundance Distribution Derived from the Two Stellar Groups
• Can Neutron-Star Mergers Explain the r-process Enrichment in Globular Clusters?
• Constraints on the Distance Moduli, Helium and Metal Abundances, and Ages of Globular Clusters from their RR Lyrae and Non-Variable Horizontal-Branch Stars. I. M3, M15, and M92
• The origins of light and heavy r-process elements identified by chemical tagging of metal-poor stars
• The Absolute Age of M92
• Neutron Star Mergers Are the Dominant Source of the r-process in the Early Evolution of Dwarf Galaxies
• Detailed Abundances of 15 Stars in the Metal-Poor Globular Cluster NGC 4833
• The Chemical Signature of a Relic Star Cluster in the Sextans Dwarf Spheroidal Galaxy - Implications for Near-Field Cosmology
• No Heavy Element Dispersion in the Globular Cluster M92
• The FAST discovery of an Eclipsing Binary Millisecond Pulsar in the Globular Cluster M92 (NGC 6341)
• High-resolution elemental abundance analysis of the open cluster IC 4756
• The most metal-poor Galactic globular cluster: the first spectroscopic observations of ESO280-SC06
• Constraints on the Distance Moduli, Helium and Metal Abundances, and Ages of Globular Clusters From Their RR Lyrae and Non-Variable Horizontal-Branch Stars. III. M55 and NGC 6362
• Atmospheric Parameters and Metallicities for 2191 stars in the Globular Cluster M4
• Signatures of Tidal Disruption in Ultra-Faint Dwarf Galaxies: A Combined HST, Gaia, and MMT/Hectochelle Study of Leo V
• r-process Abundance Patterns in the Globular Cluster M92
• Barium abundance in red giants of NGC 6752. Non-local thermodynamic equilibrium and three-dimensional effects
• NGC 1261: an $r$-process enhanced globular cluster from the Gaia-Enceladus event
• Formation of globular clusters with internal abundance spreads in r-process elements: strong evidence for prolonged star formation
• Peeking beneath the precision floor I: metallicity spreads and multiple elemental dispersions in the globular clusters NGC 288 and NGC 362
• Color-Magnitude Diagram Constraints on the Metallicities, Ages, and Star Formation History of the Stellar Populations in the Carina Dwarf Spheroidal Galaxy
• The First Billion Years project: gamma-ray bursts at z>5
• Models for Metal-Poor Stars with Different Initial Abundances of C, N, O, Mg, and Si. II. Application to the Colour-Magnitude Diagrams of the Globular Clusters 47 Tuc, NGC 6362, M5, M3, M55, and M92
• An outer shade of Pal: Abundance analysis of the outer halo globular cluster Palomar 13
• The heavy-elements heritage of the falling sky
• The Elusive Distance Gradient in the Ultra-Faint Dwarf Galaxy Hercules: A Combined Hubble Space Telescope and Gaia View
• Inference of multi-channel r-process element enrichment in the Milky Way using binary neutron star merger observations
• Astrometric Membership Tests for the Zinn-Newell-Gibson "UV-Bright" Stars in Galactic Globular Clusters
• M92 (NGC~6341) Is a Metal-Complex Globular Cluster with an Atypical Primordial Population
• A Photometric Study of Globular Clusters Observed by the APOGEE Survey
• A Comparative Study Between M30 and M92 : M92 Is A Merger Remnant With A Large Helium Enhancement
• Recent Advances in Understanding R-Process Nucleosynthesis in Metal-Poor Stars and Stellar Systems
• Neutron-capture elements in a sample of field metal-poor N-rich dwarfs