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Related papers: Accretion Processes

200 papers

Galaxies accrete their mass by means of both smooth accretion from the cosmic web, and the mergers of smaller entities. We wish to quantify the respective role of these two modes of accretion, which could determine the morphological types…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Benjamin L'Huillier , Francoise Combes , Benoit Semelin

Recent observations of protoplanetary disks have revealed ring-like structures that can be associated to pressure maxima. Pressure maxima are known to be dust collectors and planet migration traps. Most of planet formation works are based…

Earth and Planetary Astrophysics · Physics 2020-10-14 O. M. Guilera , Zs. Sándor , M. P. Ronco , J. Venturini , M. M. Miller Bertolami

The formation of star clusters involves the growth of smaller, gas-rich subclusters through accretion of gas from the giant molecular cloud within which the subclusters are embedded. The two main accretion mechanisms responsible for this…

Astrophysics of Galaxies · Physics 2023-03-29 Jeremy Karam , Alison Sills

In the core-accretion model, gas-giant planets form solid cores which then accrete gaseous envelopes. Tidal interactions with disk gas cause a core to undergo inward type-I migration in 10^4 to 10^5 years. Cores must form faster than this…

Astrophysics · Physics 2009-11-11 J. E. Chambers

In the core accretion scenario, a massive core forms first and then accretes an envelope. When discussing how this core forms some divergences appear. First scenarios of planet formation predict the accretion of km-sized bodies, called…

Earth and Planetary Astrophysics · Physics 2020-08-05 Natacha Brügger , Remo Burn , Gavin Coleman , Yann Alibert , Willy Benz

Pebble accretion is a new mechanism to quickly grow the cores of planets. In pebble accretion, gravity and gas drag conspire to yield large collisional cross sections for small particles in protoplanetary disks. However, before pebble…

Earth and Planetary Astrophysics · Physics 2016-02-03 Rico G. Visser , Chris W. Ormel

The gravitational instability of a dust layer is one of the scenarios for planetesimal formation. If the density of a dust layer becomes sufficiently high as a result of the sedimentation of dust grains toward the midplane of a…

Earth and Planetary Astrophysics · Physics 2015-05-14 Shugo Michikoshi , Eiichiro Kokubo , Shu-ichiro Inutsuka

The final stage of gas giant formation involves accreting gas from the parent protoplanetary disk. In general, the infalling gas likely approaches a free-fall velocity, creating an accretion shock, leading to strong shock heating and…

Earth and Planetary Astrophysics · Physics 2022-02-09 Zhuo Chen , Xue-Ning Bai

The evolution of protoplanetary discs embedded in stellar clusters depends on the age and the stellar density in which they are embedded. Stellar clusters of young age and high stellar surface density destroy protoplanetary discs by…

Earth and Planetary Astrophysics · Physics 2017-12-20 Nelson Ndugu , Bertram Bitsch , Edward Jurua

We present results of a detailed study of the rate of the accretion of planetesimals by a growing proto-Jupiter in the core-accretion model. Using a newly developed code, we accurately combine a detailed three-body trajectory calculation…

Earth and Planetary Astrophysics · Physics 2020-08-19 Morris Podolak , Nader Haghighipour , Peter Bodenheimer , Ravit Helled , Esther Podolak

We run numerical simulations to study the accretion of gas and dust grains onto gas giant planets embedded into massive protoplanetary discs. The outcome is found to depend on the disc cooling rate, planet mass, grain size and irradiative…

Earth and Planetary Astrophysics · Physics 2019-07-18 Jack Humphries , Sergei Nayakshin

Planets grow via the collisional accretion of small bodies in a protoplanetary disk. Such small bodies feel strong gas drag and their orbits are significantly affected by the gas flow and atmospheric structure around the planet. We…

Earth and Planetary Astrophysics · Physics 2021-08-24 Tatsuya Okamura , Hiroshi Kobayashi

The process of mass accretion onto Young Stellar Objects (YSOs) plays a fundamental role in determining the final stellar mass and setting the initial conditions for planet formation. Despite its critical role, our understanding of…

Solar and Stellar Astrophysics · Physics 2026-05-14 Eleonora Fiorellino , Alice Somigliana

Planetesimal accretion during planet formation is usually treated as collisionless. Such accretion from a uniform and dynamically cold disk predicts protoplanets with slow retrograde rotation. However, if the building blocks of…

Astrophysics · Physics 2009-01-19 Hilke E. Schlichting , Re'em Sari

The formation of a star is a dynamic process fed by the gravitational collapse of a molecular cloud core. Theoretical models and observations suggest that the majority of this infalling material settles into a protoplanetary disk before…

Astrophysics of Galaxies · Physics 2017-12-08 Doug Johnstone

Chondrules are primitive materials in the Solar System. They are formed in the first about 3 Myr of the Solar System's history. This timescale is longer than that of Mars formation, and it is conceivable that protoplanets, planetesimals and…

Earth and Planetary Astrophysics · Physics 2017-03-15 Yuji Matsumoto , Shoichi Oshino , Yasuhiro Hasegawa , Shigeru Wakita

Planetary bodies form by accretion of smaller bodies. It has been suggested that a very efficient way to grow protoplanets is by accreting particles of size <<km (e.g., chondrules, boulders, or fragments of larger bodies) as they can be…

Earth and Planetary Astrophysics · Physics 2015-05-19 C. W. Ormel , H. H. Klahr

The observed lifetimes of gaseous protoplanetary discs place strong constraints on gas and ice giant formation in the core accretion scenario. The approximately 10-Earth-mass solid core responsible for the attraction of the gaseous envelope…

Earth and Planetary Astrophysics · Physics 2015-06-05 Michiel Lambrechts , Anders Johansen

We investigate under what circumstances an embedded planet in a protoplanetary disc may sculpt the dust distribution such that it observationally presents as a `transition' disc. We concern ourselves with `transition' discs that have large…

Earth and Planetary Astrophysics · Physics 2015-06-19 James E. Owen

In the classical core-accretion planet formation scenario, rapid inward migration and accretion timescales of kilometer size planetesimals may not favor the formation of massive cores of giant planets before the dissipation of…

Earth and Planetary Astrophysics · Physics 2017-07-26 O. M. Guilera , Zs. Sándor