English
Related papers

Related papers: Evidence for universality in the initial planetesi…

200 papers

Dust concentration in protoplanetary disks (PPDs) is the first step towards planetesimal formation, a crucial yet highly uncertain stage in planet formation. Although the streaming instability (SI) is widely recognized as a powerful…

Earth and Planetary Astrophysics · Physics 2025-04-23 Pinghui Huang , Xue-Ning Bai

We present a model in which planetesimal disks are built from the combination of planetesimal formation and accretion of radially drifting pebbles onto existing planetesimals. In this model, the rate of accretion of pebbles onto…

Earth and Planetary Astrophysics · Physics 2015-08-19 John Moriarty , Debra Fischer

In the framework of the coagulation scenario, kilometre-sized planetesimals form by subsequent collisions of pre-planetesimals of sizes from centimetre to hundreds of metres. Pre-planetesimals are fluffy, porous dust aggregates, which are…

Earth and Planetary Astrophysics · Physics 2015-06-03 R. J. Geretshauser , R. Speith , W. Kley

The inner-most regions of circumbinary discs are unstable to a parametric instability whose non-linear evolution is hydrodynamical turbulence. This results in significant particle stirring, impacting on planetary growth processes such as…

Earth and Planetary Astrophysics · Physics 2021-10-20 Arnaud Pierens , Richard P. Nelson , Colin P. McNally

The main observational evidence for turbulence in the interstellar medium (ISM) and molecular clouds is the power-law energy spectrum for velocity fluctuations, E(k) \propto k^{\alpha}. The Kolmogorov scaling exponent, \alpha=-5/3, is…

Astrophysics of Galaxies · Physics 2015-05-13 N. Kevlahan , Ralph E. Pudritz

The formation of planetesimals via the streaming instability (SI) is a crucial step in planet formation, yet its triggering conditions and efficiency are highly sensitive to both disk properties and specific evolutionary processes. We aim…

While interstellar gas is known to be supersonically turbulent, the injection processes of this turbulence are still unclear. Many studies suggest a dominant role of gravitational instabilities. However, their effect on galaxy morphology…

Astrophysics of Galaxies · Physics 2023-04-26 Jérémy Fensch , Frédéric Bournaud , Noé Brucy , Yohan Dubois , Patrick Hennebelle , Joakim Rosdahl

In the core accretion scenario, gas giant planets are formed form solid cores with several Earth masses via gas accretion. We investigate the formation of such cores via collisional growth from kilometer-sized planetesimals in turbulent…

Earth and Planetary Astrophysics · Physics 2018-08-08 Hiroshi Kobayashi , Hidekazu Tanaka

Cold Neptunes and sub-Neptunes are among the most common products of planet formation and likely dominate the angular-momentum budgets in most planetary systems, yet their dynamical impact on planetary architectures remains poorly…

Earth and Planetary Astrophysics · Physics 2026-04-10 Ryan LoRusso , Cristobal Petrovich , Hareesh Gautham Bhaskar

At least 30\% of main sequence stars host planets with sizes of between 1 and 4 Earth radii and orbital periods of less than 100 days. We use N-body simulations including a model for gas-assisted pebble accretion and disk--planet tidal…

Planetesimal formation stage represents a major gap in our understanding of the planet formation process. The late-stage planet accretion models typically make arbitrary assumptions about planetesimals and pebbles distribution while the…

Earth and Planetary Astrophysics · Physics 2017-12-13 Joanna Drazkowska , Yann Alibert

The dynamics of planetesimals and planetary cores may be strongly influenced by density perturbations driven by magneto-rotational turbulence in their natal protoplanetary gas disks. Using the local shearing box approximation, we perform…

Earth and Planetary Astrophysics · Physics 2009-12-15 Chao-Chin Yang , Mordecai-Mark Mac Low , Kristen Menou

The terrestrial planets are believed to have formed by violent collisions of tens of lunar- to Mars-size protoplanets at time t<200 Myr after the protoplanetary gas disk dispersal (t_0). The solar system giant planets rapidly formed during…

Earth and Planetary Astrophysics · Physics 2021-01-13 David Nesvorny , Fernando V. Roig , Rogerio Deienno

The formation of planetesimals in protoplanetary disks due to collisional sticking of smaller dust aggregates has to face at least two severe obstacles, namely the rapid loss of material due to radial inward drift and particle fragmentation…

Astrophysics · Physics 2009-11-13 F. Brauer , Th. Henning , C. P. Dullemond

Previous work on protoplanetary dust growth shows halt at centimeter sizes owing to the occurrence of bouncing at velocities of $\geq$ 0.1 $ms^{-1}$ and fragmentation at velocities $\geq$ 1 $ms^{-1}$. To overcome these barriers, spatial…

Earth and Planetary Astrophysics · Physics 2017-01-18 M. Bukhari Syed , J. Blum , K. Wahlberg Jansson , A. Johansen

We develop an analytic framework to understand fragmentation in turbulent, self-gravitating media. Previously, we showed some properties of turbulence can be predicted with the excursion-set formalism. Here, we generalize to fully…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-02 Philip F. Hopkins

Streaming instability is a privileged channel to bridge the gap between collisional growth of dust grains and planetesimal formation triggered by gravity. This instability is thought to develop through its secular mode, which is long-time…

Earth and Planetary Astrophysics · Physics 2020-01-15 Etienne Jaupart , Guillaume Laibe

Kuiper belt objects show an unexpected trend, whereby large bodies have increasingly higher densities, up to five times greater than their smaller counterparts. Current explanations for this trend assume formation at constant composition,…

Planetesimal formation models often invoke the gravitational collapse of pebble clouds to overcome various barriers to grain growth and propose processes to concentrate particles sufficiently to trigger this collapse. On the other hand, the…

Earth and Planetary Astrophysics · Physics 2024-12-11 P. Segretain , H. Méheut , M. Moreira , G. Lesur , C. Robert , J. Mauxion

The streaming instability (SI), driven by aerodynamic coupling between solids and the gas under a global radial pressure gradient, concentrates solids and facilitates planetesimal formation. Unstratified simulations are commonly used to…

Earth and Planetary Astrophysics · Physics 2025-09-09 Jeonghoon Lim , Stanley A. Baronett , Jacob B. Simon , Chao-Chin Yang , Debanjan Sengupta , Orkan M. Umurhan , Wladimir Lyra
‹ Prev 1 8 9 10 Next ›