Simulating hydromagnetic processes in star formation: introducing ambipolar diffusion into an adaptive mesh refinement code

Abstract

Given the importance of simulating hydromagnetic processes that impact star formation, we have earlier developed a 3D adaptive mesh approach that allows us to include hydromagnetic processes during the formation and evolution of cores, discs, and stars in observed regions of star formation. In this paper, we take the next step in this program - namely - to develop a modified version of the 3D adaptive mesh refinement (AMR) code FLASH in which the ambipolar diffusion of the magnetic field in poorly ionized molecular gas is implemented. We approach the problem using a single-fluid approximation to simplify numerical calculations. In this paper, we present a series of test cases including oblique isothermal and non--isothermal C-shocks. We also present a study of the quasi-static collapse of an initial uniform, self-gravitating, magnetized sphere that is initially supported by its magnetic field against collapse (i.e. magnetically subcritical). Applications to the collapse of a pre-stellar Bonnor-Ebert sphere are presented in a companion paper.

to appear in MNRAS; 18 pages, 10 figures

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Cited by in corpus (28)

• Modeling Collapse and Accretion in Turbulent Gas Clouds: Implementation and Comparison of Sink Particles in AMR and SPH
• Clump morphology and evolution in MHD simulations of molecular cloud formation
• Ambipolar diffusion in low-mass star formation. I. General comparison with the ideal MHD case
• Radiation Magnetohydrodynamic Simulations of Protostellar Collapse: Non-Ideal Magnetohydrodynamic Effects and Early Formation of Circumstellar Disks
• Molecular Cloud Evolution IV: Magnetic Fields, Ambipolar Diffusion, and the Star Formation Efficiency
• Grand Design Spiral Arms in A Young Forming Circumstellar Disk
• Protostellar birth with ambipolar and ohmic diffusion
• A chemical solver to compute molecule and grain abundances and non-ideal MHD resistivities in prestellar core collapse calculations
• Rayleigh-Taylor instability in prominences from numerical simulations including partial ionization effects
• Incorporating Ambipolar and Ohmic Diffusion in the AMR MHD code RAMSES
• The early history of protostellar disks, outflows, and binary stars
• Sub-Alfvenic Non-Ideal MHD Turbulence Simulations with Ambipolar Diffusion: II. Comparison with Observation, Clump Properties, and Scaling to Physical Units
• Ambipolar diffusion in smoothed particle magnetohydrodynamics
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• DISPATCH: A Numerical Simulation Framework for the Exa-scale Era. I. Fundamentals
• Binary Star Formation and the Outflows from their Discs
• The magnetic diffusivities in 3D radiative chemo-hydrodynamic simulations of protostellar collapse
• Non-ideal MHD simulations of subcritical prestellar cores with non-equilibrium chemistry
• Non-ideal magnetohydrodynamic simulations of the first star formation: the effect of ambipolar diffusion
• The challenges of modelling microphysics: ambipolar diffusion, chemistry, and cosmic rays in MHD shocks
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• On the thermal sensitivity of binary formation in collapsing molecular clouds
• Collapse and Fragmentation of Magnetic Molecular Cloud Cores with the Enzo AMR MHD Code. II. Prolate and Oblate Cores
• Dust evolution during the protostellar collapse: influence on the coupling between the neutral gas and the magnetic field
• Magnetic Spirals in Accretion Flows Originated from Misaligned Magnetic Field
• Discs, outflows, and feedback in collapsing magnetized cores
• Numerical Methods for Simulating Star Formation
• Non-ideal MHD and protostellar feedback effects on disc formation and evolution in numerical simulations of star cluster formation