The History of R-Process Enrichment in the Milky Way

Abstract

We investigate the production sites and the enrichment history of $r$-process elements in the Galaxy, as traced by the [Eu/Fe] ratio, using the high resolution, cosmological zoom-in simulation `Eris'. At $z=0$, Eris represents a close analog to the Milky Way, making it the ideal laboratory to understand the chemical evolution of our Galaxy. Eris formally traces the production of oxygen and iron due to Type-Ia and Type-II supernovae. We include in post-processing the production of $r$-process elements from compact binary mergers. Unlike previous studies, we find that the nucleosynthetic products from compact binary mergers can be incorporated into stars of very low metallicity and at early times, even with a minimum delay time of 100 Myr. This conclusion is relatively insensitive to modest variations in the merger rate, minimum delay time, and the delay time distribution. By implementing a first-order prescription for metal-mixing, we can further improve the agreement between our model and the data for the chemical evolution of both [$\alpha$/Fe] and [Eu/Fe].We argue that compact binary mergers could be the dominant source of $r$-process nucleosynthesis in the Galaxy.

10 pages, 8 figures. Accepted for publication in ApJ

References in corpus (13)

• Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations--I. Isolated Galaxies
• Chemical enrichment in cosmological, smoothed particle hydrodynamics simulations
• Comprehensive nucleosynthesis analysis for ejecta of compact binary mergers
• A Search for Stars of Very Low Metal Abundance. VI. Detailed Abundances of 313 Metal-Poor Stars
• First Stars VIII -- Enrichment of the neutron-capture elements in the early Galaxy
• Galactic r-process enrichment by neutron star mergers in cosmological simulations of a Milky Way-mass galaxy
• Integrated Nucleosynthesis in Neutrino Driven Winds
• New Extremely Metal-Poor Stars in the Galactic Halo
• Explaining the Ba, Y, Sr, and Eu abundance scatter in metal-poor halo stars: constraints to the r-process
• Chemical mixing in smoothed particle hydrodynamics simulations
• Compact Stellar Binary Assembly in the First Nuclear Star Clusters and r-Process Synthesis in the Early Universe
• Chemodynamics of a Simulated Disc Galaxy: Initial Mass Functions and SNIa Progenitors
• The origins of light and heavy r-process elements identified by chemical tagging of metal-poor stars

Cited by in corpus (64)

• Origin of the heavy elements in binary neutron-star mergers from a gravitational wave event
• Light Curves of the Neutron Star Merger GW170817/SSS17a: Implications for R-Process Nucleosynthesis
• The Combined Ultraviolet, Optical, and Near-Infrared Light Curves of the Kilonova Associated with the Binary Neutron Star Merger GW170817: Unified Data Set, Analytic Models, and Physical Implications
• Kilonovae
• Neutron Star Mergers and Nucleosynthesis of Heavy Elements
• Electromagnetic Evidence that SSS17a is the Result of a Binary Neutron Star Merger
• Complete element abundances of nine stars in the r-process galaxy Reticulum II
• Production of the entire range of r-process nuclides by black hole accretion disc outflows from neutron star mergers
• The impact of companions on stellar evolution
• First Multimessenger Observations of a Neutron Star Merger
• A Neutron Star Binary Merger Model for GW170817/GRB170817a/SSS17a
• Advanced LIGO Constraints on Neutron Star Mergers and R-Process Sites
• r-process Production Sites as inferred from Eu Abundances in Dwarf Galaxies
• Natal Kicks and Time Delays in Merging Neutron Star Binaries - Implications for r-process nucleosynthesis in Ultra Faint Dwarfs and in the Milky Way
• $R$-process enhancements of Gaia-Enceladus in GALAH DR3
• Chemical evolution library for galaxy formation simulation
• Can neutron star mergers alone explain the r-process enrichment of the Milky Way?
• Galactic Chemical Evolution: the Impact of the 13C-pocket Structure on the s-process Distribution
• Contribution of Neutron Star Mergers to the R-process Chemical Evolution in the Hierarchical Galaxy Formation
• Simulating Neutron Star Mergers as r-process Sources in Ultra Faint Dwarf Galaxies
• Evidence for $\gtrsim 4$ Gyr timescales of neutron star mergers from Galactic archaeology
• Probing Kilonova Ejecta Properties Using a Catalog of Short Gamma-Ray Burst Observations
• The chemical evolution of r-process elements from neutron star mergers: the role of a 2-phase interstellar medium
• Measuring the delay time distribution of binary neutron stars. II. Using the redshift distribution from third-generation gravitational wave detectors network
• Dynamical ejecta of neutron star mergers with nucleonic weak processes II: Kilonova emission
• The Most Metal-poor Stars in the Magellanic Clouds are $r$-process Enhanced
• Early chemo-dynamical evolution of dwarf galaxies deduced from enrichment of r-process elements
• Abundances of neutron-capture elements in thin- and thick-disc stars in the solar neighbourhood
• "Super-Kilonovae" from Massive Collapsars as Signatures of Black-Hole Birth in the Pair-instability Mass Gap
• The R-Process Alliance: The Peculiar Chemical Abundance Pattern of RAVE J183013.5-455510
• Neutron star mergers as the astrophysical site of the r-process in the Milky Way and its satellite galaxies
• Collapsar R-Process Yields Can Reproduce [Eu/Fe] Abundance Scatter in Metal-Poor Stars
• Finding the remnants of the Milky Way's last neutron star mergers
• Exploring compact binary merger host galaxies and environments with $\mathrm{zELDA}$
• Chemical analysis of CH stars - III: Atmospheric parameters and elemental abundances
• Explosive nucleosynthesis of ultra-stripped Type Ic supernovae: application to light trans-iron elements
• Constraining Collapsar r-Process Models through Stellar Abundances
• Origin of highly $r$-process-enhanced stars in a cosmological zoom-in simulation of a Milky Way-like galaxy
• Radiogenic Heating and its Influence on Rocky Planet Dynamos and Habitability
• Impact of systematic nuclear uncertainties on composition and decay heat of dynamical and disk ejecta in compact binary mergers
• Diversity of Abundance Patterns of Light Neutron-capture Elements in Very-metal-poor Stars
• Highly r-process enhanced stars in ultra-faint dwarf galaxies
• The impact of natal kicks on galactic r-process enrichment by neutron star mergers
• Common envelope jets supernova r-process yields can reproduce $[Eu/Fe]$ abundance evolution in the Galaxy
• Neutron stars mergers in a stochastic chemical evolution model: impact of time delay distributions
• On the Impact of Neutron Star Binaries Natal-Kick Distribution on the Galactic r-process Enrichment
• The universality of the rapid neutron-capture process revealed by a possible disrupted dwarf galaxy star
• Supernova-driven turbulent metal mixing in high redshift galactic disks: metallicity fluctuations in the interstellar medium and its imprints on metal poor stars in the Milky Way
• The impact of turbulent mixing on the galactic r-process enrichment by binary neutron star mergers
• R-process Element Cosmic Rays from Neutron Star Mergers
• r-Process enrichment in the Galactic halo characterized by nucleosynthesis variation in the ejecta of coalescing neutron star binaries
• Structural effects of ${}^{34}$Na in the ${}^{33}$Na(n,$\gamma {)}^{34}$Na radiative capture reaction
• Constraints on the frequency and mass content of r-process events derived from turbulent mixing in galactic disks
• The Contribution Of Outer HI Disks To The Merging Binary Black Hole Population
• The impact of mass uncertainties on the r-process nucleosynthesis in neutron star mergers
• Detection of the actinide Th in an r-process-enhanced star with accretion origin
• Where has all the $r$-process gone? Timescales for GRB-Kilonovae to Enrich their Host Galaxies
• The neutron-capture and alpha-elements abundance ratios scatter in old stellar populations. Cosmological simulations of the stellar halo
• Assessing stellar yields in Galaxy chemical evolution: observational stellar abundance patterns
• R-process heating implementation in hydrodynamic simulations with neural networks
• Modelling the chemical evolution of the Milky Way
• Distribution of Europium in The Milky Way Disk; Its Connection to Planetary Habitability and The Source of The R-Process
• Universality and variability of the heavy r-process element abundance pattern from a nonequilibrium approach
• Implications of low neutron star merger rates for gamma-ray bursts, r-process production and Galactic double neutron stars