Drawing the line between explosion and collapse in electron-capture supernovae -- I. Impact of conductive flame speeds and ignition conditions on the explosion mechanism

Abstract

Electron-capture supernovae (ECSNe) are commonly thought to result in a collapse to a neutron star. Recent work has shown that a thermonuclear explosion is also a possible outcome. The division between the two regimes has not yet been mapped out. In this study, we investigate the conditions under which the transition from thermonuclear explosion to collapse occurs, and what physical mechanisms drive each outcome. We conducted a parameter study of 56 3D hydrodynamic simulations of ECSN in ONe white dwarfs using a level set based flame model implemented in the Leafs code. We varied both the ignition location and the central density at ignition to determine the conditions of the transition regime. Additionally, we explored two different laminar flame parameterizations and how they impact the simulation outcome. From our parameter study, we find a transition density in the range of $\log {\rho }_c^{ini}=10.0$ and $10.15$ g cm${}^{-3}$, depending on the ignition location and utilized laminar flame speed parameterization. Importantly, we find that for sufficiently high central densities, the burned ashes can sink into the core and trap large amounts of neutron-rich material in the bound remnant. In the transition regime between explosion and collapse, we find that the laminar flame speed plays a critical role by suppressing the formation of instabilities and thereby reducing the nuclear energy generation needed to overcome the collapse. We find that a thermonuclear explosion is possible for a wide range of parameters, whereby a more off-center ignition allows for higher central densities to still result in an explosion. Both the conditions at ignition and the flame physics are critical in determining the outcome. Detailed 3D hydrodynamic simulations of the preceding stellar evolution and the ignition process of the thermonuclear flame are necessary to accurately predict the outcome of ECSNe.

16 pages, 9 figures, accepted for publication in A&A

References in corpus (53)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Giant Planets, Oscillations, Rotation, and Massive Stars
• Modules for Experiments in Stellar Astrophysics (MESA): Binaries, Pulsations, and Explosions
• Shell-model calculations of stellar weak interaction rates: II. Weak rates for nuclei in the mass range A=45-65 in supernovae environment
• Three-dimensional delayed-detonation models with nucleosynthesis for Type Ia supernovae
• The Effects of Binary Evolution on the Dynamics of Core Collapse and Neutron-Star Kicks
• Double-detonation sub-Chandrasekhar supernovae: can minimum helium shell masses detonate the core?
• Three-dimensional pure deflagration models with nucleosynthesis and synthetic observables for Type Ia supernovae
• Electron-capture supernovae as the origin of elements beyond iron
• Equation of state of fully ionized electron-ion plasmas. II. Extension to relativistic densities and to the solid phase
• Advanced burning stages and fate of 8-10 Mo stars
• A three-dimensional deflagration model for Type Ia supernovae confronted with observations
• Super-AGB Stars and their role as Electron Capture Supernova progenitors
• Type Ia Supernova Explosions in Binary Systems: A Review
• Full-star Type Ia supernova explosion models
• Dynamics of shock propagation and nucleosynthesis conditions in O-Ne-Mg core supernovae
• Do electron-capture supernovae make neutron stars? First multidimensional hydrodynamic simulations of the oxygen deflagration
• Stellar GADGET: A smooth particle hydrodynamics code for stellar astrophysics and its application to Type Ia supernovae from white dwarf mergers
• A localised subgrid scale model for fluid dynamical simulations in astrophysics I: Theory and numerical tests
• A localised subgrid scale model for fluid dynamical simulations in astrophysics II: Application to type Ia supernovae
• Carbon Ignition in Type Ia Supernovae: II. A Three-Dimensional Numerical Model
• Thermal Runaway During the Evolution of ONeMg Cores towards Accretion-Induced Collapse
• An unusual white dwarf star may be a surviving remnant of a subluminous Type Ia supernova
• Multi-spot ignition in type Ia supernova models
• The Sensitivity of Core-Collapse Supernovae to Nuclear Electron Capture
• The C-flame Quenching by Convective Boundary Mixing in Super-AGB Stars and the Formation of Hybrid C/O/Ne White Dwarfs and SN Progenitors
• Remnants and ejecta of thermonuclear electron-capture supernovae: Constraining oxygen-neon deflagrations in high-density white dwarfs
• High-Resolution Simulations of Convection Preceding Ignition in Type Ia Supernovae Using Adaptive Mesh Refinement
• Type Ia supernovae from exploding oxygen-neon white dwarfs
• Astrophysical weak-interaction rates for selected $A=20$ and $A=24$ nuclei
• Partly burnt runaway stellar remnants from peculiar thermonuclear supernovae
• Low Mach Number Modeling of Type Ia Supernovae. IV. White Dwarf Convection
• Discovery of an Exceptionally Strong $\beta$-Decay Transition of ${}^{20}$F and Implications for the Fate of Intermediate-Mass Stars
• Evolution of ONeMg Core in Super-AGB Stars towards Electron-Capture Supernovae: Effects of Updated Electron-Capture Rate
• Electron Capture Supernovae of Super-AGB Stars: Sensitivity on Input Physics
• The Importance of Urca-process Cooling in Accreting ONe White Dwarfs
• The white dwarf's carbon fraction as a secondary parameter of Type Ia supernovae
• The physics of Core-Collapse Supernovae: explosion mechanism and explosive nucleosynthesis
• The Evolution towards Electron-capture Supernovae: the Flame Propagation and the Pre-bounce Electron-neutrino Radiation
• A New Model for Electron-Capture Supernovae in Galactic Chemical Evolution
• Neutrino and gravitational wave signal of a delayed-detonation model of Type Ia supernovae
• Thermonuclear explosions of rapidly differentially rotating white dwarfs: Candidates for superluminous Type Ia supernovae?
• Synthetic observables for electron-capture supernovae and low-mass core collapse supernovae
• A transiting brown dwarf in a 2 hour orbit
• Electron fraction constraints based on Nuclear Statistical Equilibrium with beta equilibrium
• Hydrodynamic Simulations of Electron-capture Supernovae: Progenitor and Dimension Dependence
• Models of pulsationally assisted gravitationally confined detonations with different ignition conditions
• Astrophysical S factor of {${}^{12}$C($\alpha ,\gamma$)${}^{16}$O} Calculated with the Reduced R-matrix Theory
• Type Ia supernovae from non-accreting progenitors
• Residual Carbon in Oxygen-Neon White Dwarfs and its Implications for Accretion-Induced Collapse
• The impact of the uncertainties in the 12C(α,γ)16O reaction rate on the evolution of low- to intermediate-mass stars
• Thermonuclear and Electron-Capture Supernovae from Stripped-Envelope Stars
• Laminar Flame Speeds in Degenerate Oxygen-Neon Mixtures

Cited by in corpus (1)

• Collapse of Magnetized White Dwarfs as site of Heavy Element Formation and Kilonova Signal