English
Related papers

Related papers: Magnetic Diffusion in Star Formation

200 papers

The lower solar atmosphere consists of partially ionized turbulent plasmas harbouring velocity field, magnetic field and current density fluctuations. The correlations amongst these small scale fluctuations give rise to large scale flows…

Solar and Stellar Astrophysics · Physics 2009-04-23 V. Krishan , S. Masuda

We consider the effects of an outflow on radiation escaping from the infalling envelope around a massive protostar. Using numerical radiative transfer calculations, we show that outflows with properties comparable to those observed around…

Astrophysics · Physics 2009-11-10 Mark R. Krumholz , Christopher F. McKee , Richard I. Klein

We examine the impact of the magnetic field on Population III star formation by varying the magnetic field strength. We perform simulations with magnetic field strengths ranging from $10^{-20}$ G to $10^{-4}$ G, in addition to a model…

Solar and Stellar Astrophysics · Physics 2025-05-28 Masahiro N. Machida , Shingo Hirano , Shantanu Basu

Observed protostellar outflows exhibit a variety of asymmetrical features, including remarkable unipolar outflows and bending outflows. Revealing the formation and early evolution of such asymmetrical protostellar outflows, especially the…

Solar and Stellar Astrophysics · Physics 2024-01-08 Daisuke Takaishi , Yusuke Tsukamoto , Miyu Kido , Shigehisa Takakuwa , Yoshiaki Misugi , Yuki Kudoh , Yasushi Suto

Protoplanetary disks form through angular momentum conservation in collapsing dense cores. In this work, we perform the first simulations with a maximal resolution down to the astronomical unit (au) of protoplanetary disk formation, through…

Recent numerical analysis of Keplerian disk formation in turbulent, magnetized cloud cores by Santos-Lima, de Gouveia Dal Pino, & Lazarian (2012) demonstrated that reconnection diffusion is an efficient process to remove the magnetic flux…

Astrophysics of Galaxies · Physics 2015-06-12 R. Santos-Lima , E. M. de Gouveia Dal Pino , A. Lazarian

The large-scale magnetic field threading an accretion disk plays an important role in launching jets/outflows. The field may probably be advected inwards by the plasma in the accretion disk from the ambient environment (interstellar medium…

High Energy Astrophysical Phenomena · Physics 2019-02-27 Jiawen Li , Xinwu Cao

We use magnetic collapse models to place some constraints on the formation and angular momentum evolution of circumstellar disks which are embedded in magnetized cloud cores. Previous models have shown that the early evolution of a…

Astrophysics · Physics 2009-10-30 Shantanu Basu

Under ideal MHD conditions the magnetic field strength should be correlated with density in the interstellar medium (ISM). However, observations indicate that this correlation is weak. Ambipolar diffusion can decrease the flux-to-mass ratio…

Astrophysics · Physics 2009-11-10 F. Heitsch , E. G. Zweibel , A. D. Slyz , J. E. G. Devriendt

Protoplanetary disks dissipate rapidly after the central star forms, on time-scales comparable to those inferred for planet formation. In order to allow the formation of planets, disks must survive the dispersive effects of UV and X-ray…

Earth and Planetary Astrophysics · Physics 2019-01-24 U. Gorti , R. Liseau , Zs. Sandor , C. Clarke

Galaxy disk formation must incorporate the multiphase nature of the interstellar medium. The resulting two-phase structure is generated and maintained by gravitational instability and supernova energy input, which yield a source of…

Astrophysics · Physics 2016-08-30 Joseph Silk

The interstellar magnetic field strength and gas density are observed to be correlated, but there is a large dispersion in this relation. In particular, the magnetic field is often observed to be weaker than expected. It is usually assumed…

Astrophysics · Physics 2009-11-06 Ellen G. Zweibel

Neutron stars contain persistent, ordered magnetic fields that are the strongest known in the Universe. However, their magnetic fluxes are similar to those in magnetic A and B stars and white dwarfs, suggesting that flux conservation during…

Astrophysics · Physics 2009-11-13 Andreas Reisenegger

The grand question of star and planet formation is the distribution of magnetic flux in the protoplanetary disks. To answer it, a detailed self-consistent chemical evolution is needed to describe the magnetic dissipation in the collapsing…

Solar and Stellar Astrophysics · Physics 2017-07-26 Natalia Dzyurkevich , Benoit Commercon , Pierre Lesaffre , Dimitry Semenov

Recent theoretical studies have suggested that a magnetic field may play a crucial role in the first star formation in the universe. However, the influence of the magnetic field on the first star formation has yet to be understood well. In…

Astrophysics of Galaxies · Physics 2021-05-26 Kenji Eric Sadanari , Kazuyuki Omukai , Kazuyuki Sugimura , Tomoaki Matsumoto , Kengo Tomida

Misalignment between rotation and magnetic field has been suggested to be one type of physical mechanisms which can easen the effects of magnetic braking during collapse of cloud cores leading to formation of protostellar disks. However,…

Solar and Stellar Astrophysics · Physics 2022-04-06 Weixiao Wang , Miikka S. Väisälä , Hsien Shang , Ruben Krasnopolsky , Zhi-Yun Li , Ka Ho Lam , Feng Yuan

Large-scale dipolar surface magnetic fields have been detected in a fraction of OB stars, however only few stellar evolution models of massive stars have considered the impact of these fossil fields. We are performing 1D hydrodynamical…

Solar and Stellar Astrophysics · Physics 2017-11-15 Z. Keszthelyi , G. A. Wade , V. Petit

Both stars and planets can lose mass through an expansive wind outflow, often constrained or channeled by magnetic fields that form a surrounding magnetosphere. The very strong winds of massive stars are understood to be driven by…

Solar and Stellar Astrophysics · Physics 2022-11-01 Stan Owocki

Molecular clouds, the birthplaces of stars in galaxies, form dynamically from the diffuse atomic gas of the interstellar medium (ISM). The ISM is also threaded by magnetic fields which have a large impact on its dynamics. In particular,…

Astrophysics of Galaxies · Physics 2015-09-14 Robi Banerjee , Bastian Körtgen

Magnetic field is playing an important role at all stages of star evolution from star formation to the endpoints. The main effects are briefly reviewed. We also show that O-type stars have large convective envelopes, where convective dynamo…

Astrophysics · Physics 2009-11-13 André Maeder , Georges Meynet , Cyril Georgy , Sylvia Ekström