Formation of dust filaments in the diffuse envelopes of molecular clouds

Abstract

The path to understanding star formation processes begins with the study of the formation of molecular clouds. The outskirts of these clouds are characterized by low column densities that allow the penetration of ultraviolet radiation, resulting in a non-negligible ionization fraction and the charging of the small dust grains that are mixed with the gas; this diffuse phase is then coupled to the ambient magnetic field. Despite the general assumption that dust and gas are tightly correlated, several observational and theoretical studies have reported variations in the dust-to-gas ratio toward diffuse and cold clouds. In this work, we present the implementation of a new charged particles module for analyzing the dust dynamics in molecular cloud envelopes. We study the evolution of a single population of small charged grains (0.05 $\mu$m) in the turbulent, magnetized molecular cloud envelope using this module. We show that variations in the dust-to-gas ratio arise due to the coupling of the grains with the magnetic field, forming elongated dust structures decoupled from the gas. This emphasizes the importance of considering the dynamics of charged dust when simulating the different phases of the interstellar medium, especially for star formation studies.

arXiv comment16 pages, 14 figures, accepted for publication in ApJ

References in corpus (56)

• Scikit-learn: Machine Learning in Python
• scikit-image: Image processing in Python
• From filamentary clouds to prestellar cores to the stellar IMF: Initial highlights from the Herschel Gould Belt survey
• Interstellar Turbulence I: Observations and Processes
• The Interstellar Environment of our Galaxy
• Athena: A New Code for Astrophysical MHD
• Characterizing interstellar filaments with Herschel in IC5146
• Herschel view of the Taurus B211/3 filament and striations: Evidence of filamentary growth?
• Photoelectric Emission from Interstellar Dust: Grain Charging and Gas Heating
• Phantom: A smoothed particle hydrodynamics and magnetohydrodynamics code for astrophysics
• Inefficient star formation through turbulence, magnetic fields and feedback
• The Formation and Destruction of Molecular Clouds and Galactic Star Formation
• Magnetic fields in protoplanetary disks
• Magnetically Aligned HI Fibers and the Rolling Hough Transform
• Planck 2018 results. XI. Polarized dust foregrounds
• Magnetically Regulated Star Formation in 3D: The Case of Taurus Molecular Cloud Complex
• Supernova Driving. I. The Origin of Molecular Cloud Turbulence
• Planck 2018 results. XII. Galactic astrophysics using polarized dust emission
• Helical Fields and Filamentary Molecular Clouds II - Axisymmetric Stability and Fragmentation
• Particle-Gas Dynamics with Athena: Method and Convergence
• New 3-D gas density maps of NaI and CaII interstellar absorption within 300pc
• A new, large-scale map of interstellar reddening derived from HI emission
• The molecular cloud lifecycle
• Interstellar dust charging in dense molecular clouds: cosmic ray effects
• High angular resolution Sunyaev-Zel'dovich observations of MACS J1423.8+2404 with NIKA: Multiwavelength analysis
• A Model for the Onset of Self-gravitation and Star Formation in Molecular Gas Governed by Galactic Forces: I. Cloud-scale Gas Motions
• Formation of the Young Massive Cluster R136 triggered by Tidally-driven Colliding HI Flows
• Efficient Production of S${}_8$ in Interstellar Ices: The effects of cosmic ray-driven radiation chemistry and non-diffusive bulk reactions
• The dynamical evolution of molecular clouds near the Galactic Centre - II. Spatial structure and kinematics of simulated clouds
• GHIGLS: HI mapping at intermediate Galactic latitude using the Green Bank Telescope
• A closer look at the "characteristic" width of molecular cloud filaments
• Molecular and Atomic Gas in the Large Magellanic Cloud II. Three-dimensional Correlation between CO and HI
• Relative Alignment Between the Magnetic Field and Molecular Gas Structure in the Vela C Giant Molecular Cloud using Low and High Density Tracers
• From diffuse gas to dense molecular cloud cores
• Evidence for dust evolution within the Taurus Complex from Spitzer images
• Evidence for supernova feedback sustaining gas turbulence in nearby star-forming galaxies
• Grain Dynamics In Magnetized Interstellar Gas
• Penetration of cosmic rays into dense molecular clouds: role of diffuse envelope
• The Heating of Test Particles in Numerical Simulations of Alfvenic Turbulence
• Three-fluid plasmas in star formation I. Magneto-hydrodynamic equations
• Ubiquitous Instabilities of Dust Moving in Magnetized Gas
• Dust/gas correlations from Herschel Observations
• The Dynamics of Charged Dust in Magnetized Molecular Clouds
• Can We Trust the Dust? Evidence of Dust Segregation in Molecular Clouds
• Dust-to-gas ratio, $X_{\mathrm{CO}}$ factor and CO-dark gas in the Galactic anticentre: an observational study
• Variations between Dust and Gas in the Diffuse Interstellar Medium
• Some Stars are Totally Metal: A New Mechanism Driving Dust Across Star-Forming Clouds, and Consequences for Planets, Stars, and Galaxies
• A Particle Module for the PLUTO Code: III -- Dust
• Dust grain dynamics in C-Type shock waves in molecular clouds
• Nonlinear Evolution of the Resonant Drag Instability in Magnetized Gas
• Simulating the Diverse Instabilities of Dust in Magnetized Gas
• The Thermodynamics of Molecular Cloud Fragmentation: Star Formation Under Non-Milky Way Conditions
• Dusty Molecular Cloud Collapse in the Presence of Alfvén Waves
• Interstellar extinction in Orion. Variation of the strength of the UV bump across the complex
• Variation of the ultraviolet extinction law across the Taurus-Auriga star forming complex. A GALEX based study
• Charged grains and Kelvin Helmholtz instability in molecular clouds

Cited by in corpus (5)

• Dust dynamics in RAMSES -- I. Methods and turbulent acceleration
• Implementation of dust particles in three-dimensional magnetohydrodynamics simulation: Dust dynamics in a collapsing cloud core
• Effects of dust grain size distribution on the abundances of CO and H${}_2$ in galaxy evolution
• Dust growth in molecular cloud envelopes: a numerical approach
• Gas phase Elemental abundances in Molecular cloudS (GEMS). X. Observational effects of turbulence on the chemistry of molecular clouds