2D End-to-End Modeling of Kilonovae from Binary Neutron Star Merger Remnants
arXiv:2508.00062 · doi:10.1093/mnras/staf1529
Abstract
We investigate the kilonova emission resulting from outflows produced in a three-dimensional (3D) general-relativistic magnetohydrodynamic (GRMHD) simulation of a hypermassive neutron star (HMNS) remnant. We map the outflows into the FLASH hydrodynamics code to model their expansion in axisymmetry, and study the effects of employing different -process heating rates. Except for the highest heating rate prescription, we find no significant differences with respect to overall ejecta dynamics and morphology compared to the simulation without heating. Once homologous expansion is attained, typically after 2s for these ejecta, we map the outflows to the Sedona radiative transfer code and compute the spectral evolution of the kilonova and broadband light curves in various Legacy Survey of Space and Time (LSST) bands. The kilonova properties depend on the remnant lifetime, with peak luminosities and peak timescales increasing for longer-lived remnants that produce more massive ejecta. For all models, there is a strong dependence of both the bolometric and broadband light curves on the viewing angle. While the short-lived (12ms) remnant produces higher luminosities when viewed from angles closer to the pole, longer-lived remnants (240ms and 2.5s) are more luminous when viewed from angles closer to the equator. Our results highlight the importance of self-consistent, long-term modeling of merger ejecta, and taking viewing-angle dependence into account when interpreting observed kilonova light curves. We find that magnetized outflows from a HMNS -- if it survives long enough -- could explain blue kilonovae, such as the blue emission seen in AT2017gfo.
20 pages, 18 figures, published by MNRAS
References in corpus (64)
- GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
- Origin of the heavy elements in binary neutron-star mergers from a gravitational wave event
- Swope Supernova Survey 2017a (SSS17a), the Optical Counterpart to a Gravitational Wave Source
- 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
- Spectroscopic identification of r-process nucleosynthesis in a double neutron star merger
- The Physics of Gamma-Ray Bursts and Relativistic Jets
- A kilonova as the electromagnetic counterpart to a gravitational-wave source
- The X-ray counterpart to the gravitational wave event GW 170817
- Light Curves of the Neutron Star Merger GW170817/SSS17a: Implications for R-Process Nucleosynthesis
- Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger
- The Emergence of a Lanthanide-Rich Kilonova Following the Merger of Two Neutron Stars
- Optical emission from a kilonova following a gravitational-wave-detected neutron-star merger
- 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
- Neutrino-driven winds from neutron star merger remnants
- Kilonovae
- The discovery of the electromagnetic counterpart of GW170817: kilonova AT 2017gfo/DLT17ck
- The Electromagnetic Counterpart of the Binary Neutron Star Merger LIGO/VIRGO GW170817. V. Rising X-ray Emission from an Off-Axis Jet
- Neutron Star Mergers and Nucleosynthesis of Heavy Elements
- Time Dependent Monte Carlo Radiative Transfer Calculations For 3-Dimensional Supernova Spectra, Lightcurves, and Polarization
- Kilonova from post-merger ejecta as an optical and near-infrared counterpart of GW170817
- 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
- Kilonova Light Curves from the Disk Wind Outflows of Compact Object Mergers
- The dynamical mass ejection from binary neutron star mergers: Radiation-hydrodynamics study in general relativity
- MASTER optical detection of the first LIGO/Virgo neutron stars merging GW170817
- Merger and Mass Ejection of Neutron-Star Binaries
- The Dynamics of Binary Neutron Star Mergers and of GW170817
- Follow up of GW170817 and its electromagnetic counterpart by Australian-led observing programs
- J-GEM observations of an electromagnetic counterpart to the neutron star merger GW170817
- Jet collimation in the ejecta of double neutron star merger: new canonical picture of short gamma-ray bursts
- Impact of an improved neutrino energy estimate on outflows in neutron star merger simulations
- Evolution of magnetized, differentially rotating neutron stars: Simulations in full general relativity
- Properties of Kilonovae from Dynamical and Post-Merger Ejecta of Neutron Star Mergers
- Necessary Conditions for Short Gamma-Ray Burst Production in Binary Neutron Star Mergers
- Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration
- GRB170817A associated with GW170817: multifrequency observations and modeling of prompt gamma-ray emission
- A magnetar engine for short GRBs and kilonovae
- Neutron Star Merger Remnants
- Axisymmetric Radiative Transfer Models of Kilonovae
- The evolution of binary neutron star post-merger remnants: a review
- Modeling Kilonova Light Curves: Dependence on Nuclear Inputs
- Monte Carlo Radiation Hydrodynamics with Implicit Methods
- Monte-Carlo neutrino transport in neutron star merger simulations
- End-to-end kilonova models of neutron-star mergers with delayed black-hole formation
- Optical measurement of superluminal motion in the neutron-star merger GW170817
- A low-mass binary neutron star: long-term ejecta evolution and kilonovae with weak blue emission
- Kilonova Detectability with Wide-Field Instruments
- Inclination Dependence of Kilonova Light Curves from Globally Aspherical Geometries
- GRMHD simulations of neutron-star mergers with weak interactions: r-process nucleosynthesis and electromagnetic signatures of dynamical ejecta
- Neutrino emission from binary neutron star mergers: characterizing light curves and mean energies
- Self-consistent 3D radiative transfer for kilonovae: directional spectra from merger simulations
- Flares, jets and quasi-periodic outbursts from neutron star merger remnants
- Estimating outflow masses and velocities in merger simulations: impact of r-process heating and neutrino cooling
- 3D radiative transfer kilonova modelling for binary neutron star merger simulations
- Radiation hydrodynamics modeling of kilonovae with SNEC
- -process Nucleosynthesis and Kilonovae from Hypermassive Neutron Star Remnants
- Electromagnetic counterparts of binary neutron star mergers leading to a strongly magnetized long-lived remnant neutron star
- Long-Term Simulations of Dynamical Ejecta: Homologous Expansion and Kilonova Properties
- The impact of r-process heating on the dynamics of neutron star merger accretion disc winds and their electromagnetic radiation
- Long-lived neutron-star remnants from asymmetric binary neutron star mergers: element formation, kilonova signals and gravitational waves
- Cautionary tales on heating-rate prescriptions in kilonovae
- Secular Outflows from Long-Lived Neutron Star Merger Remnants