2016/11/30 by Chao‐Chin Yang, Chao-Chin Yang, Anders Johansen +1 · 13 citations
Chemical Engineering · Physics and Astronomy · #Advanced Combustion Engine Technologies #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Dimensionless quantity #Drag #Geology #Instability #Mechanics #Metallicity #Particle (ecology) #Physics #Planet #Planetesimal #Stars #Streaming instability #astro-ph.EP
paper · pdf · doi:10.1051/0004-6361/201630106
published as A&A 606, A80 (2017) · A&A, in press. 16 pages, 19 figures, 2 tables
arxiv created 2017/06/29 · openalex publication_date 2017/10/01 · arxiv updated 2017/10/18 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/06
Laboratory experiments indicate that direct growth of silicate grains via mutual collisions can only produce particles up to roughly millimeters in size. On the other hand, recent simulations of the streaming instability have shown that mm/cm-sized particles require an excessively high metallicity for dense filaments to emerge. Using a numerical algorithm for stiff mutual drag force, we perform simulations of small particles with significantly higher resolutions and longer simulation times than in previous investigations. We find that particles of dimensionless stopping time τs = 10-2 and 10-3 – representing cm- and mm-sized particles interior of the water ice line – concentrate themselves via the streaming instability at a solid abundance of a few percent. We thus revise a previously published critical solid abundance curve for the regime of τs ≪ 1. The solid density in the concentrated regions reaches values higher than the Roche density, indicating that direct collapse of particles down to mm sizes into planetesimals is possible. Our results hence bridge the gap in particle size between direct dust growth limited by bouncing and the streaming instability.