Conditions for justifying single-fluid approximation for charged and neutral dust fluids and a smoothed particle magnetohydrodynamics method for dust-gas mixture

Abstract

We describe a numerical scheme for magnetohydrodynamics simulations of dust-gas mixture by extending smoothed particle magnetohydrodynamics. We employ the single-species particle approach to describe dust-gas mixture with several modifications from the previous studies. We assume that the charged and neutral dusts can be treated as single-fluid and the electro-magnetic force acts on the gas and that on the charged dust is negligible. The validity of these assumption in the context of protostar formation is not obvious and is extensively evaluated. By investigating the electromagnetic force and electric current with terminal velocity approximation, it is found that as the dust size increases, the contribution of dust to them becomes smaller and negligible. We conclude that our assumptions of the electro-magnetic force on the dusts is negligible are valid for the dust size with a d & 10μm. On the other hand, they do not produce the numerical artifact for the dust a d . 10μm in envelope and disk where the perfect coupling between gas and dusts realizes. However, we also found that our assumptions may break down in outflow (or under environment with very strong magnetic field and low density) for the dust a d . 10μm. We conclude that our assumptions are valid in almost all cases where macroscopic dust dynamics is important in the context of protostar formation. We conduct numerical tests of dusty wave, dusty magnetohydrodynamics shock, and gravitational collapse of magnetized cloud core with our simulation code. The results show that our numerical scheme well reproduces the dust dynamics in the magnetized medium.

arXiv comment21 pages 11 figures. accepted in ApJ

References in corpus (51)

• Rapid Coagulation of Porous Dust Aggregates Outside the Snow Line: A Pathway to Successful Icy Planetesimal Formation
• Dust Properties of Protoplanetary Disks in the Taurus-Auriga Star Forming Region from Millimeter Wavelengths
• Modelling discontinuities and Kelvin-Helmholtz instabilities in SPH
• PROSAC: A Submillimeter Array Survey of Low-Mass Protostars. I. Overview of Program: Envelopes, Disks, Outflows and Hot Cores
• Dust coagulation and fragmentation in molecular clouds. I. How collisions between dust aggregates alter the dust size distribution
• Numerical Magnetohydrodynamics in Astrophysics: Algorithm and Tests for One-Dimensional Flow
• Magnetic fields in protoplanetary disks
• Dust grain growth in rho-Ophiuchi protoplanetary disks
• Electric charging of dust aggregates and its effect on dust coagulation in protoplanetary disks
• Mechanism of Magnetic Flux Loss in Molecular Clouds
• The Ubiquity of Micrometer-Sized Dust Grains in the Dense Interstellar Medium
• Radiation Magnetohydrodynamic Simulations of Protostellar Collapse: Non-Ideal Magnetohydrodynamic Effects and Early Formation of Circumstellar Disks
• Can non-ideal magnetohydrodynamics solve the magnetic braking catastrophe?
• Effects of Ohmic and ambipolar diffusion on the formation and evolution of the first cores, protostars and circumstellar discs
• Two-Fluid MHD Simulations of Converging HI Flows in the Interstellar Medium. I: Methodology and Basic Results
• Bridging the gap: disk formation in the Class 0 phase with ambipolar diffusion and Ohmic dissipation
• Grain growth in the envelopes and disks of Class I protostars
• Bimodality of circumstellar disk evolution induced by Hall current
• Grain Growth and Density Distribution of the Youngest Protostellar Systems
• Direct evidence of dust growth in L183 from MIR light scattering
• Decoupling of Magnetic Fields in Collapsing Protostellar Envelopes and Disk Formation and Fragmentation
• Dusty gas with one fluid
• A chemical solver to compute molecule and grain abundances and non-ideal MHD resistivities in prestellar core collapse calculations
• The early evolution of viscous and self-gravitating circumstellar disks with a dust component
• Three-fluid plasmas in star formation II. Momentum transfer rate coefficients
• Effects of radiation transfer on the structure of self-gravitating disks, their fragmentation and evolution of the fragments
• Dusty gas with SPH - II. Implicit timestepping and astrophysical drag regimes
• The impact of the Hall effect during cloud core collapse:implications for circumstellar disk evolution
• Is the dust-to-gas ratio constant in molecular clouds?
• The nonisothermal stage of magnetic star formation. II. Results
• The collapse of a molecular cloud core to stellar densities using radiation non-ideal magnetohydrodynamics
• Effect of Grain Size on Differential Desorption of Volatile Species and on Non-ideal MHD Diffusivity
• Smoothed particle magnetohydrodynamics with a Riemann solver and the method of characteristics
• DUSTYBOX and DUSTYWAVE: Two test problems for numerical simulations of two fluid astrophysical dust-gas mixtures
• Protostellar collapse: the conditions to form dust rich protoplanetary disks
• Condition for the formation of micron-sized dust grains in dense molecular cloud cores
• Dusty gas with one fluid in smoothed particle hydrodynamics
• On the dynamics of dust during protostellar collapse
• Gravitoviscous protoplanetary disks with a dust component. I. The importance of the inner sub-au region
• Disc formation and fragmentation using radiative non-ideal magnetohydrodynamics
• The impact of non-ideal magnetohydrodynamics on binary star formation
• The Dynamics of Charged Dust in Magnetized Molecular Clouds
• Does misalignment between magnetic field and angular momentum enhance or suppress circumstellar disk formation?
• Hall Effect in Protostellar Disc Formation and Evolution
• Ionization: a possible explanation for the difference of mean disk sizes in star-forming regions
• Hall effect-driven formation of gravitationally unstable discs in magnetized molecular cloud cores
• The Interplay between Ambipolar Diffusion and Hall Effect on Magnetic Field Decoupling and Protostellar Disc Formation
• Early evolution of disk, outflow, and magnetic field of young stellar objects: Impact of dust model
• An explicit scheme for ohmic dissipation with smoothed particle magneto-hydrodynamics
• Dependence of Hall Coefficient on Grain Size and Cosmic Ray Rate and Implication for Circumstellar Disk Formation
• Magnetic field and early evolution of circumstellar disks

Cited by in corpus (16)

• "Ash-fall" induced by molecular outflow in protostar evolution
• Modeling disks and magnetic outflows around a forming massive star: I. Investigating the two layer-structure of the accretion disk
• Co-evolution of dust grains and protoplanetary disks
• Dust coagulation and fragmentation in a collapsing cloud core and their influence on non-ideal magnetohydrodynamic effects
• Impact of dust size distribution including large dust grains on magnetic resistivity: an analytical approach
• Mixing is easy: New insights for cosmochemical evolution from pre-stellar core collapse
• Implementation of dust particles in three-dimensional magnetohydrodynamics simulation: Dust dynamics in a collapsing cloud core
• Filling in the Gaps: Can Gravitationally Unstable Discs Form the Seeds of Gas Giant Planets?
• Impact of turbulence intensity and fragmentation velocity on dust particle size evolution and non-ideal magnetohydrodynamics effects
• Dust Motion and Possibility of Dust Growth in a Growing Circumstellar Disk
• First observations of warm and cold methanol in Class 0/I proto-brown dwarfs
• Star-forming environments in smoothed particle magnetohydrodynamics simulations I: Clump extraction and properties
• Single Fluid vs. Multifluid: Comparison between single fluid and multifluid dust models for disc planet interactions
• Special Relativistic Smoothed Particle Hydrodynamics Based on Riemann Solver
• "Ashfall" Induced by Molecular Outflow in Protostar Evolution. II. Analytical Study on the Maximum Size of Dust Grains Lifted by Outflows
• Synthetic Polarization Maps of an Outflow Zone from Magnetohydrodynamic Simulations