Skip to Main content Skip to Navigation
New interface
Journal articles

Protostellar collapse simulations in spherical geometry with dust coagulation and fragmentation.

Abstract : We model the coagulation and fragmentation of dust grains during the protostellar collapse with our newly developed shark code. It solves the gas-dust hydrodynamics in a spherical geometry and the coagulation/fragmentation equation. It also computes the ionization state of the cloud and the Ohmic, ambipolar and Hall resistivities. We find that the dust size distribution evolves significantly during the collapse, large grain formation being controlled by the turbulent differential velocity. When turbulence is included, only ambipolar diffusion remains efficient at removing the small grains from the distribution, brownian motion is only efficient as a standalone process. The macroscopic gas-dust drift is negligible for grain growth and only dynamically significant near the first Larson core. At high density, we find that the coagulated distribution is unaffected by the initial choice of dust distribution. Strong magnetic fields are found to enhance the small grains depletion, causing an important increase of the ambipolar diffusion. This hints that the magnetic field strength could be regulated by the small grain population during the protostellar collapse. Fragmentation could be effective for bare silicates, but its modeling relies on the choice of ill-constrained parameters. It is also found to be negligible for icy grains. When fragmentation occurs, it strongly affects the magnetic resistivities profiles. Dust coagulation is a critical process that needs to be fully taken into account during the protostellar collapse. The onset and feedback of fragmentation remains uncertain and its modeling should be further investigated.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03867373
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Wednesday, November 23, 2022 - 12:24:37 PM
Last modification on : Friday, November 25, 2022 - 3:32:52 AM

Links full text

Identifiers

Citation

Ugo Lebreuilly, Valentin Vallucci-Goy, Vincent Guillet, Maxime Lombart, Pierre Marchand. Protostellar collapse simulations in spherical geometry with dust coagulation and fragmentation.. Monthly Notices of the Royal Astronomical Society, 2022, ⟨10.1093/mnras/stac3220⟩. ⟨insu-03867373⟩

Share

Metrics

Record views

0