English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We have studied formation of planetesimals at a radial pressure bump in aprotoplanetary disk created by radially inhomogeneous magnetorotationalinstability (MRI), through three-dimensional resistive MHD simulationsincluding dust particles. In our previous papers, we showed that theinhomogeneous MRI developing in non-uniform structure of magnetic field ormagnetic resistivity can transform the local gas flow in the disk to aquasi-steady state with local rigid rotation that is no more unstable againstthe MRI. Since the outer part of the rigid rotation is super-Keplerian flow, aquasi-static pressure bump is created and dust concentration is expected there.In this paper, we perform simulations of the same systems, adding dustparticles that suffer gas drag and modulate gas flow via the back-reaction ofthe gas drag (dust drag). We use O(10^7) super-particles, each of whichrepresents many dust particles with sizes of centimeter to meter. We have foundthat the dust drag suppresses turbulent motion to decrease the velocitydispersion of the dust particles while it broadens the dust concentratedregions to limit peaky dust concentration, compared with the simulation withoutthe dust drag. We found that reduction in the velocity dispersion) is dominatedover the suppression in particle concentration. For meter-size particles withthe friction time ~1/Omega, where Omega is Keplerian frequency, thegravitational instability of the dust particles that may lead to planetesimalformation is expected. For such a situation, we further introduced theself-gravity of dust particles to the simulation to demonstrate that severalgravitationally bound clumps are actually formed. Through analytical arguments,we found that the planetesimal formation from meter-sized dust particles can bepossible at ~5AU, if dust spatial density is a few times larger than that inthe minimum mass solar nebula.

Planetesimal Formation at the Boundary Between Steady Super/Sub-Keplerian Flow Created by Inhomogeneous Growth of Magnetorotational Instability