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Related papers: Star Formation and the Hall Effect

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We investigate numerically the combined effects of supersonic turbulence, strong magnetic fields and ambipolar diffusion on cloud evolution leading to star formation. We find that, in clouds that are initially magnetically subcritical,…

Astrophysics · Physics 2009-11-10 Zhi-Yun Li , Fumitaka Nakamura

The role of outflows in the formation of stars and the protostellar disks that generate them is a central question in astrophysics. Outflows are associated with star formation across the entire stellar mass spectrum. In this review, we…

Solar and Stellar Astrophysics · Physics 2019-12-13 Ralph E. Pudritz , Tom P. Ray

Are magnetic fields important in primordial star formation? Assuming that star formation occurs via an accretion disk that is turbulent, initially because of local gravitational instability, we calculate the disk structure for realistic…

Astrophysics · Physics 2009-11-10 Jonathan C. Tan , Eric G. Blackman

(Abridged) Context. Most massive stars are located in multiple stellar systems. Magnetic fields are believed to be essential in the accretion and ejection processes around single massive protostars. Aims. Our aim is to unveil the influence…

Solar and Stellar Astrophysics · Physics 2023-05-24 R. Mignon-Risse , M. González , B. Commerçon

We review the properties of turbulent molecular clouds (MCs), focusing on the physical processes that influence star formation (SF). MC formation appears to occur during large-scale compression of the diffuse ISM driven by supernovae,…

Astrophysics · Physics 2007-05-23 J. Ballesteros-Paredes , R. S. Klessen , M. -M. Mac Low , E. Vazquez-Semadeni

It is established that the formation of rotationally supported disks during the main accretion phase of star formation is suppressed by a moderately strong magnetic field in the ideal MHD limit. Non-ideal MHD effects are expected to weaken…

Astrophysics · Physics 2011-02-11 Richard R. Mellon , Zhi-Yun Li

We investigate whether or not the low ionisation fractions in molecular cloud cores can solve the `magnetic braking catastrophe', where magnetic fields prevent the formation of circumstellar discs around young stars. We perform…

Solar and Stellar Astrophysics · Physics 2016-02-03 James Wurster , Daniel J. Price , Matthew R. Bate

The theory of the formation of the first stars in the Universe, the so-called Population III (Pop III), has until now largely neglected the impact of magnetic fields. Complementing a series of recent studies of the magneto-hydrodynamic…

Astrophysics of Galaxies · Physics 2022-09-07 Cynthia R. Saad , Volker Bromm , Mounib El Eid

Star formation is a complex process involving the interplay of many physical effects, including gravity, turbulent gas dynamics, magnetic fields and radiation. Our understanding of the process has improved substantially in recent years,…

Astrophysics of Galaxies · Physics 2015-05-18 Daniel J. Price , Matthew R. Bate

[Abridged] Theoretical and numerical studies of star formation have shown that magnetic field (B) has a strong influence on both disk formation and fragmentation; even a relatively low B can prevent these processes. However, very few…

Solar and Stellar Astrophysics · Physics 2015-06-12 Marc Joos , Patrick Hennebelle , Andrea Ciardi , Sebastien Fromang

Star formation is inefficient. Recent advances in numerical simulations and theoretical models of molecular clouds show that the combined effects of interstellar turbulence, magnetic fields and stellar feedback can explain the low…

Solar and Stellar Astrophysics · Physics 2020-02-12 Christoph Federrath

We study role of the Hall diffusion in the magnetic star-disc interaction. In a simplified steady state configuration, the total torque is calculated in terms of the fastness parameter and a new term because of the Hall diffusion. We show…

Solar and Stellar Astrophysics · Physics 2015-05-30 Mohsen Shadmehri

During the past decade the dynamical importance of magnetic fields in molecular clouds has been increasingly recognized, as observational evidence has accumulated. However, how a magnetic field affect star formation is still unclear.…

Astrophysics of Galaxies · Physics 2020-09-15 C. Y. Law , H. -b. Li , Z. Cao , C. -Y. Ng

We report results from twelve simulations of the collapse of a molecular cloud core to form one or more protostars, comprising three field strengths (mass-to-flux ratios, {\mu}, of 5, 10, and 20) and four field geometries (with values of…

Solar and Stellar Astrophysics · Physics 2017-08-28 Benjamin T. Lewis , Matthew R. Bate

The gas from which stars form is magnetized, and strong magnetic fields can efficiently transport angular momentum. Most theoretical models of this phenomenon find that it should prevent formation of large (>100 AU), rotationally-supported…

Solar and Stellar Astrophysics · Physics 2015-06-12 Mark R. Krumholz , Richard M. Crutcher , Charles L. H. Hull

The formation of protoplanetary discs during the collapse of molecular dense cores is significantly influenced by angular momentum transport, notably by the magnetic torque. In turn, the evolution of the magnetic field is determined by…

Astrophysics of Galaxies · Physics 2017-02-01 Patrick Hennebelle , Benoit Commercon , Gilles Chabrier , Pierre Marchand

We present our current understanding of the formation and early evolution of protostars, protoplanetary disks, and the driving of outflows as dictated by the interplay of magnetic fields and partially ionized gas in molecular cloud cores.…

Solar and Stellar Astrophysics · Physics 2022-09-29 Yusuke Tsukamoto , Anaëlle Maury , Benoît Commerçon , Felipe O. Alves , Erin G. Cox , Nami Sakai , Tom Ray , Bo Zhao , Masahiro N. Machida

Magnetic diffusion in accretion flows changes the structure and angular momentum of the accreting material. We present two power law similarity solutions for flattened accretion flows in the presence of magnetic diffusion: a…

Solar and Stellar Astrophysics · Physics 2015-06-11 Catherine Braiding , Mark Wardle

Our current understanding of the physical processes of star formation is reviewed, with emphasis on processes occurring in molecular clouds like those observed nearby. The dense cores of these clouds are predicted to undergo gravitational…

Astrophysics · Physics 2009-11-10 Richard B. Larson

Magnetic fields are believed to play an important role in controlling the stability and contraction of dense condensations of gas and dust leading to the formation of stars and planetary systems. In the present study, the magnetic field of…