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Related papers: A Solution to the Protostellar Accretion Problem

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This paper reviews current theoretical work on the various stages of accretion in protostars, and the relationship of these ideal stages to the spectral classes of observed protostellar systems. I discuss scaling relationships that have…

Astrophysics · Physics 2009-10-30 Eve C. Ostriker

Measurements of accretion rates onto planetary mass objects may distinguish between different planet formation mechanisms, which predict different accretion histories. In this Letter, we use \HST/WFC3 UVIS optical photometry to measure…

Solar and Stellar Astrophysics · Physics 2015-06-18 Yifan Zhou , Gregory J. Herczeg , Adam L. Kraus , Stanimir Metchev , Kelle Cruz

Massive protostars grow and evolve under the effect of rapid accretion of circumstellar gas and dust, falling at high rates ($\ge 10^{-4}$-$10^{-3}\, \rm M_{\odot}\, \rm yr^{-1}$). This mass infall has been shown, both numerically and…

Solar and Stellar Astrophysics · Physics 2019-01-16 D. M. A. Meyer , L. Haemmerlé , E. I. Vorobyov

Fragmentation of protostellar disks controls the growth of protostars and plays a key role in determining the final mass of newborn stars. In this paper, we investigate the structure and gravitational stability of the protostellar disks in…

Astrophysics of Galaxies · Physics 2015-06-18 Kei E. I. Tanaka , Kazuyuki Omukai

There is currently no accepted theoretical framework for the formation of the most massive stars, and the manner in which protostars continue to accrete and grow in mass beyond \sim10Msun is still a controversial topic. In this study we use…

This paper identifies constraints on the growth of a small planetary core (0.3 M$_{\oplus}$) that accretes millimeter-sized pebbles from a gaseous disk. We construct time-dependent spherical envelope models that capture physical processes…

Earth and Planetary Astrophysics · Physics 2020-09-08 Mohamad Ali-Dib , Christopher Thompson

Competitive accretion occurs when stars in a cluster accrete from a shared reservoir of gas. The competition arises due to the relative attraction of stars as a function of their mass and location in the cluster. The low relative motions of…

Astrophysics · Physics 2015-11-11 Ian A. Bonnell

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

Accretion disks around active galactic nuclei are potentially unstable to star formation at large radii. We note that when the compact objects formed from some of these stars spiral into the central supermassive black hole, there is no…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Alexander J. Dittmann , M. Coleman Miller

We calculate the evolution of cloud cores embedded in different envelopes to investigate environmental effects on the mass accretion rate onto protostars. As the initial state, we neglect the magnetic field and cloud rotation, and adopt…

Solar and Stellar Astrophysics · Physics 2023-01-11 Shingo Nozaki , Masahiro N. Machida

We show that for young stars which are still accreting and for which measurements of stellar age, disc mass and accretion rate are available, nominal disc age (Disc Age = Disc Mass / Accretion Rate) is approximately equal to the stellar…

Solar and Stellar Astrophysics · Physics 2015-05-30 Michael Jones , Jim Pringle , Richard Alexander

Newly formed stars are often observed to possess circumstellar disks, from which mass continues to be accreted onto the star and fed into outflowing jets, and which eventually may evolve into dusty debris disks and planetary systems. Recent…

Astrophysics · Physics 2007-05-23 A. Konigl

Variable accretion in young stellar objects reveals itself photometrically and spectroscopically over a continuum of timescales and amplitudes. Most dramatic are the large outbursts (e.g., FU Ori, V1647 Ori, and EX Lup type events), but…

Solar and Stellar Astrophysics · Physics 2023-11-20 William J. Fischer , Lynne A. Hillenbrand , Gregory J. Herczeg , Doug Johnstone , Ágnes Kóspál , Michael M. Dunham

The evidence of a relation between the mass accretion rate and the disk mass is established for young, Class II pre-main sequence stars. This observational result opened an avenue to test theoretical models and constrain the initial…

Protostellar outflows and jets are almost ubiquitous characteristics during the mass accretion phase, and encode the history of stellar accretion, complex-organic molecule (COM) formation, and planet formation. Episodic jets are likely…

We compare the angular momentum extracted by a wind from a pre-main-sequence star to the torques arising from the interaction between the star and its Keplerian accretion disk. We find that the wind alone can counteract the spin-up torque…

Astrophysics · Physics 2016-08-30 Sean Matt , Ralph E. Pudritz

Accretion onto Classical T Tauri stars is thought to take place through the action of magnetospheric processes, with gas in the inner disk being channeled onto the star's surface by the stellar magnetic field lines. Young stars are known to…

Solar and Stellar Astrophysics · Physics 2017-04-05 Connor Robinson , James Owen , Catherine Espaillat , Fred Adams

The majority of stars are part of gravitationally bound stellar systems, such as binaries. Observations of protobinary systems constrain the conditions that lead to stellar multiplicity and subsequent orbital evolution. We report…

Solar and Stellar Astrophysics · Physics 2019-10-04 Felipe O. Alves , Paola Caselli , Josep M. Girart , Dominique Segura-Cox , Gabriel A. P. Franco , Anika Schmiedeke , Bo Zhao

Observations indicate that massive stars form in regions of very high surface density, ~1 g cm^-2. Clusters containing massive stars and globular clusters have a comparable column density. The total pressure in clouds of such a column…

Astrophysics · Physics 2008-11-26 Christopher F. McKee , Jonathan C. Tan

The early evolution of protostellar, star-forming discs, including their density structure, turbulence, magnetic dynamics, and accretion variability, remains poorly understood. We present high-resolution magnetohydrodynamic simulations,…

Solar and Stellar Astrophysics · Physics 2025-08-28 Trey Qingyun Yang , Christoph Federrath