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Related papers: Protostellar Disk Formation Enabled by Weak, Misal…

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Protoplanetary disks are quasi-steady structures whose evolution and dispersal determine the environment for planet formation. I review the theory of protoplanetary disk evolution and its connection to observations. Substantial progress has…

Solar and Stellar Astrophysics · Physics 2011-08-25 Philip J. Armitage

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

Dense, star-forming, cores of molecular clouds are observed to be significantly magnetized. A realistic magnetic field of moderate strength has been shown to suppress, through catastrophic magnetic braking, the formation of a rotationally…

Astrophysics of Galaxies · Physics 2015-05-28 Zhi-Yun Li , Ruben Krasnopolsky , Hsien Shang

The galactic magnetic field is commonly supposed to be due to a dynamo acting on some large scale seed field. A major difficulty with this idea is that estimates of reasonable seed field strengths tend to be quite low, on the order of…

Astrophysics · Physics 2007-05-23 Ethan T. Vishniac

The driving mechanism of protostellar outflows and jets and their effects on the star formation process obtained from recent theoretical and numerical studies are described. Low-velocity outflows are driven by an outer region of the…

Astrophysics of Galaxies · Physics 2017-11-02 Masahiro N. Machida

Building on our previous hydrodynamic study of the angular momenta of cloud cores formed during gravitational collapse of star-forming molecular gas in our previous work, we now examine core properties assuming ideal magnetohydrodynamics…

Solar and Stellar Astrophysics · Physics 2020-04-29 Aleksandra Kuznetsova , Lee Hartmann , Fabian Heitsch

The standard picture for the formation of disk galaxies has come to face a number of problems related to angular momentum. Numerical simulations produce disks that are too small, and analytical models predict too much low angular momentum…

Astrophysics · Physics 2007-05-23 Frank C. van den Bosch

We present simulations of the supernova-driven turbulent interstellar medium (ISM) in a simulation domain of volume $(256\,{\rm pc})^3$ within which we resolve the formation of protostellar accretion disks and their stellar cores to spatial…

Understanding the physics of how stars form is a highly-prioritized goal of modern Astrophysics, in part because star formation is linked to both galactic dynamics on large scales and to the formation of planets on small scales. It is…

We argue that the first stars may have spanned the conventional mass range rather than be identified with the Very Massive Objects (100-1000 solar masses) favoured by numerical simulations. Specifically, we find that magnetic field…

Astrophysics · Physics 2008-11-26 Joseph Silk , Mathieu Langer

We review the current status of studies on accretion and protoplanetary disks of young stars with large-scale magnetic fields. Observational data on magnetic fields of the disks are compiled and analysed. Modern analytical and numerical MHD…

Solar and Stellar Astrophysics · Physics 2024-01-26 Sergey A. Khaibrakhmanov

Are the kG-strength magnetic fields observed in young stars a fossil field left over from their formation or are they generated by a dynamo? We use radiation non-ideal magnetohydrodynamics simulations of the gravitational collapse of a…

Solar and Stellar Astrophysics · Physics 2018-09-12 James Wurster , Matthew R. Bate , Daniel J. Price

Non-ideal magnetohydrodynamics (MHD) is the dominant process. We investigate the effect of magnetic fields (ideal and non-ideal) and turbulence (sub- and transsonic) on the formation of circumstellar discs that form nearly simultaneously…

Solar and Stellar Astrophysics · Physics 2020-06-03 James Wurster , Benjamin T. Lewis

The formation of circumstellar disks is investigated using three-dimensional resistive magnetohydrodynamic simulations, in which the initial prestellar cloud has a misaligned rotation axis with respect to the magnetic field. We examine the…

Solar and Stellar Astrophysics · Physics 2020-08-05 Shingo Hirano , Yusuke Tsukamoto , Shantanu Basu , Masahiro N. Machida

Magnetic fields play a vital role in numerous astrophysical processes such as star formation and the interstellar medium. In particular, their role in the formation and evolution of galaxies is not well understood. This paper presents…

Astrophysics of Galaxies · Physics 2021-12-10 Huai-Hsuan Chiu , Ke-Jung Chen

We follow the ambipolar-diffusion--driven formation and evolution of a fragment in a magnetically supported molecular cloud, until a hydrostatic protostellar core forms at its center. This problem was formulated in Paper I. We determine the…

Astrophysics · Physics 2011-02-11 Konstantinos Tassis , Telemachos Ch. Mouschovias

Angular momentum transport by magnetic fields is important for formation and evolution of protoplanetary disks. The effects of magnetic fields are suppressed due to non-ideal magnetohydrodynamic (MHD) effects such as ambipolar diffusion and…

Solar and Stellar Astrophysics · Physics 2025-05-15 Erika Nishio , Kengo Tomida , Yuki Kudoh , Shigeo S. Kimura

We consider formation of accretion disks from a realistically turbulent molecular gas using 3D MHD simulations. In particular, we analyze the effect of the fast turbulent reconnection described by the Lazarian & Vishniac (1999) model for…

Solar and Stellar Astrophysics · Physics 2016-03-16 Diego F. González-Casanova , Reinaldo Santos-Lima , Alexander Lazarian

The role of magnetic fields for the formation of planets is reviewed. Protoplanetary disc turbulence driven by the magnetorotational instability has a huge influence on the early stages of planet formation. Small dust grains are transported…

Earth and Planetary Astrophysics · Physics 2015-05-13 Anders Johansen

The presence of giant gaseous planets that reside in close proximity to their host stars may be a consequence of large-scale radial migration through the proto-planetary nebulae. Within the context of this picture, significant orbital…

Earth and Planetary Astrophysics · Physics 2015-06-17 Konstantin Batygin , Fred C. Adams