Results 1 to 10 of about 1,046 (208)
Inferring the Magnetic Field from the Rayleigh–Taylor Instability
The Astrophysical Journal, 2023 By extending the potential approach of Layzer and Goncharov to the magnetohydrodynamics equations, we find the nonlinear solutions to the single-mode Rayleigh–Taylor instability subjected to uniform magnetic fields at various inclinations. This allows us
Benoît-Joseph Gréa, Antoine Briard
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Magnetohydrodynamic Simulations of the Supernova Remnant G1.9+0.3
The Astrophysical Journal, 2023 The youngest Galactic supernova remnant G1.9+0.3 shows a discrete feature between its radio and X-ray morphologies. The observed radio morphology features a single maximum in the north, while the X-ray observation shows two opposite “ears” on the east ...
Shaobo Zhang +4 more
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Global MHD Simulations of the Time-dependent Corona
The Astrophysical Journal, 2023 We describe, test, and apply a technique to incorporate full-Sun, surface flux evolution into an MHD model of the global solar corona. Requiring only maps of the evolving surface flux, our method is similar to that of Lionello et al., but we introduce ...
Roberto Lionello +7 more
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Rotation in Event Horizon Telescope Movies
The Astrophysical Journal, 2023 The Event Horizon Telescope (EHT) has produced images of M87* and Sagittarius A*, and will soon produce time sequences of images, or movies. In anticipation of this, we describe a technique to measure the rotation rate, or pattern speed Ω _p , from ...
Nicholas S. Conroy +9 more
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The Athena++ Adaptive Mesh Refinement Framework: Multigrid Solvers for Self-gravity
The Astrophysical Journal Supplement Series, 2023 We describe the implementation of multigrid solvers in the Athena++ adaptive mesh refinement (AMR) framework and their application to the solution of the Poisson equation for self-gravity.
Kengo Tomida, James M. Stone
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Influence of Crustal Magnetic Fields on Horizontal Plasma Transport and Ion Escape on Mars
The Astrophysical Journal, 2023 Owing to its unevenly distributed crustal fields, Mars acts as a unique obstacle to the solar wind. In the presence of the crustal fields, the transport of the planetary ions on the dayside ionosphere exhibits north–south asymmetry.
Guokan Li +5 more
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Implementation of Chemistry in the Athena++ Code
The Astrophysical Journal Supplement Series, 2023 Chemistry plays a key role in many aspects of astrophysical fluids. Atoms and molecules are agents for heating and cooling, determine the ionization fraction, serve as observational tracers, and build the molecular foundation of life.
Munan Gong +8 more
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Robust Field-level Likelihood-free Inference with Galaxies
The Astrophysical Journal, 2023 We train graph neural networks to perform field-level likelihood-free inference using galaxy catalogs from state-of-the-art hydrodynamic simulations of the CAMELS project.
Natalí S. M. de Santi +14 more
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Striped Jets in Post–Neutron Star Merger Systems
The Astrophysical Journal, 2023 Models invoking magnetic reconnection as the particle acceleration mechanism within relativistic jets often adopt a gradual energy dissipation profile within the jet. However, such a profile has yet to be reproduced in first-principles simulations.
Emma Kaufman +4 more
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The Astrophysical Journal, 2023 Nonequilibrium ionization (NEI) is essentially required for astrophysical plasma diagnostics once the plasma status departs from the assumption of ionization equilibrium.
Chengcai Shen +2 more
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