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Title: On the feeding zone of planetesimal formation by the streaming instability

Abstract

The streaming instability is a promising mechanism to overcome the barriers in direct dust growth and lead to the formation of planetesimals. Most previous studies of the streaming instability, however, were focused on a local region of a protoplanetary disk with a limited simulation domain such that only one filamentary concentration of solids has been observed. The characteristic separation between filaments is therefore not known. To address this, we conduct the largest-scale simulations of the streaming instability to date, with computational domains up to 1.6 gas scale heights both horizontally and vertically. The large dynamical range allows the effect of vertical gas stratification to become prominent. We observe more frequent merging and splitting of filaments in simulation boxes of high vertical extent. We find multiple filamentary concentrations of solids with an average separation of about 0.2 local gas scale heights, much higher than the most unstable wavelength from linear stability analysis. This measures the characteristic separation of planetesimal forming events driven by the streaming instability and thus the initial feeding zone of planetesimals.

Authors:
;  [1]
  1. Lund Observatory, Department of Astronomy and Theoretical Physics, Lund University, Box 43, SE-22100 Lund (Sweden)
Publication Date:
OSTI Identifier:
22365160
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 792; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTEROIDS; CONCENTRATION RATIO; DIFFUSION BARRIERS; ELEMENT ABUNDANCE; FEEDING; HYDRODYNAMICS; INSTABILITY; PLANETS; PROTOPLANETS; SIMULATION; STABILITY; WAVELENGTHS

Citation Formats

Yang, Chao-Chin, and Johansen, Anders, E-mail: ccyang@astro.lu.se, E-mail: anders@astro.lu.se. On the feeding zone of planetesimal formation by the streaming instability. United States: N. p., 2014. Web. doi:10.1088/0004-637X/792/2/86.
Yang, Chao-Chin, & Johansen, Anders, E-mail: ccyang@astro.lu.se, E-mail: anders@astro.lu.se. On the feeding zone of planetesimal formation by the streaming instability. United States. doi:10.1088/0004-637X/792/2/86.
Yang, Chao-Chin, and Johansen, Anders, E-mail: ccyang@astro.lu.se, E-mail: anders@astro.lu.se. Wed . "On the feeding zone of planetesimal formation by the streaming instability". United States. doi:10.1088/0004-637X/792/2/86.
@article{osti_22365160,
title = {On the feeding zone of planetesimal formation by the streaming instability},
author = {Yang, Chao-Chin and Johansen, Anders, E-mail: ccyang@astro.lu.se, E-mail: anders@astro.lu.se},
abstractNote = {The streaming instability is a promising mechanism to overcome the barriers in direct dust growth and lead to the formation of planetesimals. Most previous studies of the streaming instability, however, were focused on a local region of a protoplanetary disk with a limited simulation domain such that only one filamentary concentration of solids has been observed. The characteristic separation between filaments is therefore not known. To address this, we conduct the largest-scale simulations of the streaming instability to date, with computational domains up to 1.6 gas scale heights both horizontally and vertically. The large dynamical range allows the effect of vertical gas stratification to become prominent. We observe more frequent merging and splitting of filaments in simulation boxes of high vertical extent. We find multiple filamentary concentrations of solids with an average separation of about 0.2 local gas scale heights, much higher than the most unstable wavelength from linear stability analysis. This measures the characteristic separation of planetesimal forming events driven by the streaming instability and thus the initial feeding zone of planetesimals.},
doi = {10.1088/0004-637X/792/2/86},
journal = {Astrophysical Journal},
number = 2,
volume = 792,
place = {United States},
year = {Wed Sep 10 00:00:00 EDT 2014},
month = {Wed Sep 10 00:00:00 EDT 2014}
}
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