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Related papers: Non-steady Accretion in Protostars

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A simple model of gas accretion in young galaxy disks suggests that fast turbulent motions can be driven by accretion energy for a time t_acc~2(epsilon^{0.5} GM^2/xi V^3)^{0.5} where epsilon is the fraction of the accretion energy going…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Bruce G. Elmegreen , Andreas Burkert

Core accretion and disk instability require giant protoplanets to form in the presence of disk gas. Protoplanet migration models generally assume disk masses low enough that the disk's self-gravity can be neglected. However, disk…

Earth and Planetary Astrophysics · Physics 2015-06-12 Alan P. Boss

Gravitational instability plays an important role in driving gas accretion in massive protostellar discs. Particularly strong is the global gravitational instability, which arises when the disc mass is of order 0.1 of the mass of the…

Astrophysics of Galaxies · Physics 2015-05-20 D. Harsono , R. D. Alexander , Yuri Levin

How embedded, actively accreting low-mass protostars accrete their mass is still greatly debated. Observations are now piecing together the puzzle of embedded protostellar accretion, in particular with new facilities in the near-infrared.…

Solar and Stellar Astrophysics · Physics 2024-12-25 Brandt A. L. Gaches , Jonathan C. Tan , Anna L. Rosen , Rolf Kuiper

In young circumstellar disks, accretion--the inspiral of disk material onto the central star--is important for both the buildup of stellar masses and the outcome of planet formation. Although the existence of accretion is well documented,…

Solar and Stellar Astrophysics · Physics 2018-09-19 Joan R. Najita , Edwin A. Bergin

Recent high-resolution simulations demonstrate that disks around primordial protostars easily fragment in the accretion phase before the protostars accrete less than a solar mass. To understand why the gravitational instability generally…

Astrophysics of Galaxies · Physics 2021-04-21 Kazutaka Kimura , Takashi Hosokawa , Kazuyuki Sugimura

We report on the first global three-dimensional (3D) MHD simulations of disk accretion onto a rotating magnetized star through the Rayleigh-Taylor instability. The star has a dipole field misaligned relative to the rotation axis by a small…

Astrophysics · Physics 2018-01-17 Marina M. Romanova , Akshay K. Kulkarni , Richard V. E. Lovelace

Context. Due to the presence of magnetic fields, protostellar jets/outflows are a natural consequence of accretion onto protostars. They are expected to play an important role for star and protoplanetary disk formation. Aims. We aim to…

Solar and Stellar Astrophysics · Physics 2023-12-07 U. Lebreuilly , P. Hennebelle , A. Maury , M. González , A. Traficante , R. Klessen , L. Testi , S. Molinari

We present the first results of a global axisymmetric simulation of accretion onto rotating magnetized stars from a turbulent, MRI-driven disk. The angular momentum is transported outward by the magnetic stress of the turbulent flow with a…

Solar and Stellar Astrophysics · Physics 2015-05-27 Marina M. Romanova , Galina V. Ustyugova , Alexander V. Koldoba , Richard V. E. Lovelace

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

Gravitational instability (GI) is typically studied in cooling-dominated discs, often modelled using simplified prescriptions such as $\beta$-cooling. In this paper, we investigate the onset and evolution of GI in accretion discs subject to…

Earth and Planetary Astrophysics · Physics 2025-06-19 Cristiano Longarini , Daniel Price , Kaitlin M. Kratter , Giuseppe Lodato , Cathie J. Clarke

We combine the output of hydrodynamical simulations of Population III star cluster formation with stellar evolution models, and calculate the evolution of protostars experiencing variable mass accretion rates due to interactions within a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Rowan J. Smith , Takashi Hosokawa , Kazuyuki Omukai , Simon C. O. Glover , Ralf S. Klessen

Recent high-resolution observations have revealed filamentary accretion flows (``streamers'') in protoplanetary disks older than 1 Myr, suggesting that late-stage interstellar gas infall (late infall) may affect disk evolution and stellar…

Earth and Planetary Astrophysics · Physics 2026-05-27 W. Ooyama , R. Nakatani , T. Hosokawa , H. Mitani

Discs of gas and dust are ubiquitous around protostars. Hypothetical disc viscosity is thought to cause the gas and dust to accrete onto the star. Turbulence within the disc might be the source of this disc viscosity. However, observed…

Earth and Planetary Astrophysics · Physics 2023-10-31 Kurt Liffman

Young stellar systems orbiting in the potential of their birth cluster can accrete from the dense molecular interstellar medium during the period between the star's birth and the dispersal of the cluster's gas. Over this time, which may…

Solar and Stellar Astrophysics · Physics 2014-11-20 Nickolas Moeckel , Henry B. Throop

High-mass young stellar objects exhibit episodic accretion bursts similar to their low-mass counterparts. Understanding these outbursts is crucial for elucidating massive star formation and disk evolution around high-mass protostars. We…

Solar and Stellar Astrophysics · Physics 2025-09-10 Vardan Elbakyan , Dennis Wehner , Rolf Kuiper , Sergei Nayakshin , Alessio Caratti o Garatti , Zhen Guo

In this Letter we present a theoretical scenario to explain the steep correlation between disk accretion rates and stellar masses observed in pre-main sequence stars. We show that the correlations and spread observed in the two best studied…

Astrophysics · Physics 2009-11-11 C. P. Dullemond , A. Natta , L. Testi

Angular momentum in protostellar discs can be transported either radially, through turbulence induced by the magnetorotational instability (MRI), or vertically, through the torque exerted by a large-scale magnetic field. We present a model…

Astrophysics · Physics 2009-11-13 Raquel Salmeron , Arieh Königl , Mark Wardle

FO Aquarii, an asynchronous magnetic cataclysmic variable (intermediate polar) went into a low-state in 2016, from which it slowly and steadily recovered without showing dwarf nova outbursts. This requires explanation since in a low-state,…

Solar and Stellar Astrophysics · Physics 2017-09-27 Jean-Marie Hameury , Jean-Pierre Lasota

In accretion disks with large-scale ordered magnetic fields, the magnetorotational instability (MRI) is marginally suppressed, so other processes may drive angular momentum transport leading to accretion. Accretion could then be driven by…

High Energy Astrophysical Phenomena · Physics 2018-05-16 Megan D. Marshall , Mark J. Avara , Jonathan C. McKinney
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