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Title: DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE

Abstract

A major goal over the last decade has been understanding which multidimensional effects are crucial in facilitating core-collapse supernova (CCSN) explosions. Unfortunately, much of this work has necessarily assumed axisymmetry. In this work, we present analyses of simplified two-dimensional (2D) and three-dimensional (3D) CCSN models with the goal of comparing the hydrodynamics in setups that differ only in dimension. Not surprisingly, we find many differences between 2D and 3D models. While some differences are subtle and perhaps not crucial, others are dramatic and make interpreting 2D models problematic. In particular, axisymmetric models produce excess power at the largest spatial scales, power that has been deemed critical in previous explosion models. Nevertheless, our 3D models, which have an order of magnitude less power than 2D models on large scales, explode earlier. Since explosions occur earlier in 3D than in 2D, the vigorous large-scale sloshing is either not critical in any dimension or the explosion mechanism operates differently in 2D and 3D. On the other hand, we find that the average parcel of matter in the gain region has been exposed to net heating for up to 30% longer in 3D than in 2D, an effect we attribute to the differing charactersmore » of turbulence in 2D and 3D. We suggest that this effect plays a prominent role in producing earlier explosions in 3D. Finally, we discuss a simple model for the runaway growth of buoyant bubbles that is able to quantitatively account for the growth of the shock radius and predicts a critical luminosity relation.« less

Authors:
; ;  [1];  [2]
  1. Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States)
  2. Center for Computational Relativity and Gravitation, Rochester Institute of Technology, Rochester, NY 14623 (United States)
Publication Date:
OSTI Identifier:
22126994
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 765; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTRONOMY; ASTROPHYSICS; AXIAL SYMMETRY; COMPARATIVE EVALUATIONS; COSMIC NEUTRINOS; GAIN; GRAVITATIONAL COLLAPSE; HYDRODYNAMICS; LUMINOSITY; STAR MODELS; SUPERNOVAE; THREE-DIMENSIONAL CALCULATIONS; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Dolence, Joshua C., Burrows, Adam, Murphy, Jeremiah W., and Nordhaus, Jason, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu, E-mail: jmurphy@astro.princeton.edu, E-mail: nordhaus@astro.rit.edu. DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE. United States: N. p., 2013. Web. doi:10.1088/0004-637X/765/2/110.
Dolence, Joshua C., Burrows, Adam, Murphy, Jeremiah W., & Nordhaus, Jason, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu, E-mail: jmurphy@astro.princeton.edu, E-mail: nordhaus@astro.rit.edu. DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE. United States. doi:10.1088/0004-637X/765/2/110.
Dolence, Joshua C., Burrows, Adam, Murphy, Jeremiah W., and Nordhaus, Jason, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu, E-mail: jmurphy@astro.princeton.edu, E-mail: nordhaus@astro.rit.edu. Sun . "DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE". United States. doi:10.1088/0004-637X/765/2/110.
@article{osti_22126994,
title = {DIMENSIONAL DEPENDENCE OF THE HYDRODYNAMICS OF CORE-COLLAPSE SUPERNOVAE},
author = {Dolence, Joshua C. and Burrows, Adam and Murphy, Jeremiah W. and Nordhaus, Jason, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu, E-mail: jmurphy@astro.princeton.edu, E-mail: nordhaus@astro.rit.edu},
abstractNote = {A major goal over the last decade has been understanding which multidimensional effects are crucial in facilitating core-collapse supernova (CCSN) explosions. Unfortunately, much of this work has necessarily assumed axisymmetry. In this work, we present analyses of simplified two-dimensional (2D) and three-dimensional (3D) CCSN models with the goal of comparing the hydrodynamics in setups that differ only in dimension. Not surprisingly, we find many differences between 2D and 3D models. While some differences are subtle and perhaps not crucial, others are dramatic and make interpreting 2D models problematic. In particular, axisymmetric models produce excess power at the largest spatial scales, power that has been deemed critical in previous explosion models. Nevertheless, our 3D models, which have an order of magnitude less power than 2D models on large scales, explode earlier. Since explosions occur earlier in 3D than in 2D, the vigorous large-scale sloshing is either not critical in any dimension or the explosion mechanism operates differently in 2D and 3D. On the other hand, we find that the average parcel of matter in the gain region has been exposed to net heating for up to 30% longer in 3D than in 2D, an effect we attribute to the differing characters of turbulence in 2D and 3D. We suggest that this effect plays a prominent role in producing earlier explosions in 3D. Finally, we discuss a simple model for the runaway growth of buoyant bubbles that is able to quantitatively account for the growth of the shock radius and predicts a critical luminosity relation.},
doi = {10.1088/0004-637X/765/2/110},
journal = {Astrophysical Journal},
number = 2,
volume = 765,
place = {United States},
year = {Sun Mar 10 00:00:00 EST 2013},
month = {Sun Mar 10 00:00:00 EST 2013}
}
  • We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M{sub Sun} progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effectsmore » by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.« less
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