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Related papers: Hall-magnetohydrodynamic simulations of X-ray phot…

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The transport of angular momentum by magnetic fields is a crucial physical process in formation and evolution of stars and disks. Because the ionization degree in star forming clouds is extremely low, non-ideal magnetohydrodynamic (MHD)…

Solar and Stellar Astrophysics · Physics 2015-06-23 Kengo Tomida , Satoshi Okuzumi , Masahiro N. Machida

It has recently been established that the evolution of protoplanetary disks is primarily driven by magnetized disk winds, requiring large-scale magnetic flux threading the disks. The size of such disks is expected to shrink in time, as…

Solar and Stellar Astrophysics · Physics 2021-12-08 Haifeng Yang , Xue-Ning Bai

The destabilising effect of Hall diffusion in a Keplerian disc allows the MRI to occur for much lower ionisation levels than would otherwise be possible. However, simulations suggest that the consequences for the saturated state are not as…

Earth and Planetary Astrophysics · Physics 2015-05-27 Mark Wardle , Raquel Salmeron

Non-ideal MHD effects have been shown recently as a robust mechanism of averting the magnetic braking "catastrophe" and promoting protostellar disc formation. However, the magnetic diffusivities that determine the efficiency of non-ideal…

Solar and Stellar Astrophysics · Physics 2021-05-12 Bo Zhao , Paola Caselli , Zhi-Yun Li , Ruben Krasnopolsky , Hsien Shang , Ka Ho Lam

Protoplanetary discs are thought to evolve either through angular momentum transport driven by viscous processes or through angular momentum removal induced by magnetohydrodynamic (MHD) winds. One proposed method to distinguish between…

Earth and Planetary Astrophysics · Physics 2026-02-20 Giulia Ballabio , James E. Owen

Context. Transition disks (TDs) are a type of protoplanetary disk characterized by a central dust and gas cavity. The processes behind how these cavities are formed and maintained, along with their observed high accretion rates of $10^{-8}…

Earth and Planetary Astrophysics · Physics 2025-03-05 Eleftheria Sarafidou , Oliver Gressel , Barbara Ercolano

Imaging of the dust continuum emitted from disks around nearby protostars reveals diverse substructure. In recent years, theoretical efforts have been intensified to investigate how far the intrinsic dynamics of protoplanetary disks (PPDs)…

Earth and Planetary Astrophysics · Physics 2019-05-31 Leonardo Krapp , Oliver Gressel , Pablo Benítez-Llambay , Turlough P. Downes , Gopakumar Mohandas , Martin E. Pessah

We estimate the mass loss rates of photoevaporative winds launched from the outer edge of protoplanetary discs impinged by an ambient radiation field. We focus on mild/moderate environments (the number of stars in the group/cluster is N ~…

Solar and Stellar Astrophysics · Physics 2016-02-03 Stefano Facchini , Cathie J. Clarke , Thomas G. Bisbas

We present new analytical solutions for the evolution of protoplanetary discs (PPDs) where magnetohydrodynamic (MHD) wind-driven processes dominate. Our study uses a 1D model which incorporates equations detailing angular momentum…

Astrophysics of Galaxies · Physics 2024-01-19 Mohsen Shadmehri , Fazeleh Khajenabi

The driving mechanism of massive outflows observed in high-mass star-forming regions is investigated using three-dimensional magnetohydrodynamics (MHD) and protostellar evolution calculations. In our previous paper, we showed that the mass…

Solar and Stellar Astrophysics · Physics 2018-01-31 Yuko Matsushita , Yuya Sakurai , Takashi Hosokawa , Masahiro N. Machida

Protoplanetary discs are poorly ionised due to their low temperatures and high column densities, and are therefore subject to three "non-ideal" magnetohydrodynamic effects: Ohmic dissipation, ambipolar diffusion, and the Hall effect. The…

Solar and Stellar Astrophysics · Physics 2014-07-02 Geoffroy Lesur , Matthew W. Kunz , Sebastien Fromang

We discuss a hydrodynamical model for the dispersal of protoplanetary discs around young, low mass (<1.5 M_sun) stars by photoevaporation from the central object's energetic radiation, which considers the far-ultraviolet as well as the…

Solar and Stellar Astrophysics · Physics 2015-06-03 James E. Owen , Cathie J. Clarke , Barbara Ercolano

Global evolution and dispersal of protoplanetary disks (PPDs) is governed by disk angular momentum transport and mass-loss processes. Recent numerical studies suggest that angular momentum transport in the inner region of PPDs is largely…

Earth and Planetary Astrophysics · Physics 2016-03-09 Xue-Ning Bai , Jiani Ye , Jeremy Goodman , Feng Yuan

By performing local three-dimensional MHD simulations of stratified accretion disks, we investigate disk winds driven by MHD turbulence. Initially given weak vertical magnetic fields are effectively amplified by magnetorotational…

Astrophysics · Physics 2015-05-13 T. K. Suzuki , S. Inutsuka

The Hall effect is recently shown to be efficient in magnetized dense molecular cores, and could lead to a bimodal formation of rotationally supported discs (RSDs) in the first core phase. However, how such Hall dominated systems evolve in…

Solar and Stellar Astrophysics · Physics 2020-09-17 Bo Zhao , Paola Caselli , Zhi-Yun Li , Ruben Krasnopolsky , Hsien Shang , Ka Ho Lam

The mechanisms of angular momentum transport and level of turbulence in protoplanetary disks (PPDs) are crucial for understanding many aspects of planet formation. In the recent years, it has been realized that the magneto-rotational…

Earth and Planetary Astrophysics · Physics 2020-03-11 Can Cui , Xue-Ning Bai

The magnetorotational instability (MRI) is the most promising mechanism by which angular momentum is efficiently transported outwards in astrophysical discs. However, its application to protoplanetary discs remains problematic. These discs…

Earth and Planetary Astrophysics · Physics 2015-06-16 Matthew W. Kunz , Geoffroy Lesur

High resolution X-ray spectra of black hole X-ray binaries (BHBs) show blueshifted absorption lines from disk winds which seem to be equatorial. Winds occur in the Softer (disk-dominated) states of the outburst and are less prominent or…

High Energy Astrophysical Phenomena · Physics 2016-04-27 S. Chakravorty , P-O. Petrucci , J. Ferreira , G. Henri , R. Belmont , M. Clavel , S. Corbel , J. Rodriguez , M. Coriat , S. Drappeau , J. Malzac

Giant protoplanets evacuate a gap in their host protoplanetary disc, which gas must cross before it can be accreted. A magnetic field is likely carried into the gap, potentially influencing the flow. Gap crossing has been simulated with…

Earth and Planetary Astrophysics · Physics 2015-08-06 Sarah L. Keith , Mark Wardle

We study the evolution of the protoplanetary discs (PPDs) in the presence of magnetically driven winds with the stress relations motivated by the non-ideal MHD disc simulations. Contribution of the magnetic winds in the angular momentum…

Astrophysics of Galaxies · Physics 2019-07-31 Mohsen Shadmehri , Sayyedeh Masoumeh Ghoreyshi