Particle Pileups and Planetesimal Formation

By A. Youdin, E. Chiang. 2003

149 citations recorded by the source corpus.

Solid particles in protoplanetary disks that are sufficiently supersolar in metallicity overcome turbulence generated by vertical shear to gravitationally condense into planetesimals. Supersolar metallicities result if solid particles pile up as they migrate starward as a result of aerodynamic drag. Previous analyses of aerodynamic drift rates that account for mean flow differences between gas and particles yield particle pileups. We improve on these studies not only by accounting for the collective inertia of solids relative to that of gas, but also by including the transport of angular momentum by turbulent stresses within the particle layer. These turbulent stresses are derived in a physically self-consistent manner from the structure of marginally Kelvin-Helmholtz turbulent flows. They are not calculated using the usual plate drag formulae, whose use we explain is inappropriate. Accounting for the relative inertia of solids to gas retards, but does not prevent, particle pileups and generates more spatially extended regions of metal enrichment. Turbulent transport hastens pileups. We conclude that particle pileup is a robust outcome in sufficiently passive protoplanetary disks. Connections to observations of circumstellar disks, including the Kuiper Belt, and the architectures of planetary systems are made.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/3320e9045c2426773112b296d94d72488572b39c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

Citations in the corpus

A simple model for the evolution of the dust population in protoplanetary disks (2012, background): “This leads to a pile-up effect similar to Youdin & Chiang (2004).”
The Effect of Internal Dissipation and Surface Irradiation on the Structure of Disks and the Location of the Snow Line around Sun-like Stars (2006, background): “…(“pebbles” to “boulders”) have a different intrinsic motion which is sensitively dependent on the structure (temperature, pressure gradient) and dynamical nature (tubulent versus laminar) of the nebular gas (Morfill & Voelk 1984, Supulver & Lin 2000, Youdin & Chiang, 2004, Ciesla & Cuzzi 2006).”
Forming Planetesimals in Solar and Extrasolar Nebulae (2009, background): “3.1.2 Pileups and Pressure Traps As particles of a given size drift inward, they tend to “pile up,” increasing Σp/Σg (YS, Youdin & Chiang 2004); see Figure 2.”
Accelerated planetesimal growth in self-gravitating protoplanetary discs (2004, background): “This could significantly enhance the coagulation of planetesimals into larger bodies, by increasing the planetesimal collision rates and/or by making the planetesimal subdisc become gravitationally unstable (Youdin & Shu 2002; Youdin & Chiang 2004).”
Toward Planetesimals: Dense Chondrule Clumps in the Protoplanetary Nebula (2008, background): “…the particles to be small enough that the particlerich midplane acts as a single fluid, like fog, so that its vertical density stratification stabilizes it against selfgenerated turbulence (Sekiya 1998, Sekiya and Ishitsu 2001, Youdin and Shu 2002, Sekiya and Takeda 2003, Youdin and Chiang 2004).”
PARTICLE CLUMPING AND PLANETESIMAL FORMATION DEPEND STRONGLY ON METALLICITY (2009, background): “The pebble abundance may increase as solid particles drift radially inward, converging in the inner few dozen AUs of the protoplanetary disk (Stepinski & Valageas 1996; Youdin & Chiang 2004).”
The evolution of the water distribution in a viscous protoplanetary disk (2005, background): “, 2001), trapping of particles in eddies (Klahr and Henning, 1997), buildup of particles in pressure maxima in a non-uniform nebula (Haghighipour and Boss, 2003) and gravitational instabilities in a dust layer (Goldreich and Ward, 1973; Sekiya, 1998; Youdin and Chiang, 2004).”