Magnetic Field Strength Effects on Nucleosynthesis from Neutron Star Merger Outflows

Abstract

Magnetohydrodynamic turbulence drives the central engine of post-merger remnants, potentially powering both a nucleosynthetically active disk wind and the relativistic jet behind a short gamma ray burst. We explore the impact of the magnetic field on this engine by simulating three post-merger black hole accretion disks using general relativistic magnetohydrodynamics with Monte Carlo neutrino transport, in each case varying the initial magnetic field strength. We find increasing ejecta masses associated with increasing magnetic field strength. We find that a fairly robust main r -process pattern is produced in all three cases, scaled by the ejected mass. Changing the initial magnetic field strength has a considerable effect on the geometry of the outflow and hints at complex central engine dynamics influencing lanthanide outflows. We find that actinide production is especially sensitive to magnetic field strength, with overall actinide mass fraction calculated at 1 Gyr post-merger increasing by more than a factor of six with a tenfold increase in magnetic field strength. This hints at a possible connection to the variability in actinide enhancements exhibited by metal poor, r -process-enhanced stars.

References in corpus (34)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Multi-messenger Observations of a Binary Neutron Star Merger
• Origin of the heavy elements in binary neutron-star mergers from a gravitational wave event
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. II. UV, Optical, and Near-IR Light Curves and Comparison to Kilonova Models
• The Emergence of a Lanthanide-Rich Kilonova Following the Merger of Two Neutron Stars
• Comprehensive nucleosynthesis analysis for ejecta of compact binary mergers
• Swift and NuSTAR observations of GW170817: detection of a blue kilonova
• 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
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. IV. Detection of Near-infrared Signatures of r-process Nucleosynthesis with Gemini-South
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. III. Optical and UV Spectra of a Blue Kilonova From Fast Polar Ejecta
• The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. VI. Radio Constraints on a Relativistic Jet and Predictions for Late-Time Emission from the Kilonova Ejecta
• The dynamical mass ejection from binary neutron star mergers: Radiation-hydrodynamics study in general relativity
• AT2017gfo: an anisotropic and three-component kilonova counterpart of GW170817
• Discovery of HE 1523-0901, a Strongly r-Process Enhanced Metal-Poor Star with Detected Uranium
• Equation of State in Relativistic Magnetohydrodynamics: variable versus constant adiabatic index
• Full Transport Model of GW170817-Like Disk Produces a Blue Kilonova
• Post-merger evolution of a neutron star-black hole binary with neutrino transport
• Dynamical r-process studies within the neutrino-driven wind scenario and its sensitivity to the nuclear physics input
• WHAM: A WENO-based general relativistic numerical scheme I: Hydrodynamics
• The Disc-Jet Symbiosis Emerges: Modeling the Emission of Sagittarius A* with Electron Thermodynamics
• Outflows from accretion disks formed in neutron star mergers: effect of black hole spin
• Kilonovae across the nuclear physics landscape: The impact of nuclear physics uncertainties on r-process-powered emission
• Modeling Kilonova Light Curves: Dependence on Nuclear Inputs
• Magnetohydrodynamics of Neutrino-Cooled Accretion Tori around a Rotating Black Hole in General Relativity
• Neutron-gamma competition for $\beta$-delayed neutron emission
• Nucleosynthesis and observation of the heaviest elements
• $\nu \text{bhlight}$: Radiation GRMHD for Neutrino-Driven Accretion Flows
• Following nuclei through nucleosynthesis: a novel tracing technique
• Long-term 3D-MHD Simulations of Black Hole Accretion Disks formed in Neutron Star Mergers
• The Influence of Beta Decay Rates on r-Process Observables
• Impact of systematic nuclear uncertainties on composition and decay heat of dynamical and disk ejecta in compact binary mergers
• Surrogate light curve models for kilonovae with comprehensive wind ejecta outflows and parameter estimation for AT2017gfo
• Nucleosynthesis in outflows of compact objects and detection prospects of associated kilonovae
• Characterizing $r$-Process Sites through Actinide Production

Cited by in corpus (1)

• Angle-dependent in-situ fast flavor transformations in post-neutron star merger disks