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Related papers: Reconnection Diffusion and Star Formation

200 papers

Planets appear to form in environments shaped by the gas flowing through protostellar disks to the central young stars. The flows in turn are governed by orbital angular momentum transfer. In this chapter we summarize current understanding…

Earth and Planetary Astrophysics · Physics 2015-06-18 N. J. Turner , S. Fromang , C. Gammie , H. Klahr , G. Lesur , M. Wardle , X. -N. Bai

We develop a quantitative relationship between magnetic diffusion and the level of randomness, or stochasticity, of the diffusing magnetic field in a magnetized medium. A general mathematical formulation of magnetic stochasticity in…

High Energy Astrophysical Phenomena · Physics 2019-10-23 Amir Jafari , Ethan Vishniac , Vignesh Vaikundaraman

We use numerical simulations of turbulent cluster-forming regions to study the nature of dense filamentary structures in star formation. Using four hydrodynamic and magnetohydrodynamic simulations chosen to match observations, we identify…

Astrophysics of Galaxies · Physics 2015-06-23 Helen Kirk , Ralph Pudritz , Mikhail Klassen , Samantha Pillsworth

Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation cannot be ultimately achieved without collisions, and so how turbulent…

Space Physics · Physics 2016-01-01 Y. Wang , F. S. Wei , X. S. Feng , X. J. Xu , J. Zhang , T. R. Sun , P. B. Zuo

Magnetic field amplification by a fast dynamo is seen in local box simulations of SN-driven ISM turbulence, where the self-consistent emergence of large-scale fields agrees very well with its mean-field description. We accordingly derive…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-25 Detlef Elstner , Oliver Gressel

Star formation is inefficient. Only a few percent of the available gas in molecular clouds forms stars, leading to the observed low star formation rate (SFR). The same holds when averaged over many molecular clouds, such that the SFR of…

Astrophysics of Galaxies · Physics 2016-06-13 Christoph Federrath

Magnetohydrodynamic turbulence and magnetic reconnection are ubiquitous in astrophysical environments. In most situations, these processes do not occur in isolation, but interact with each other. This renders a comprehensive theory of these…

Plasma Physics · Physics 2018-03-29 L. Comisso , Y. -M. Huang , M. Lingam , E. Hirvijoki , A. Bhattacharjee

Magnetic reconnection is a fundamental physical process in various astrophysical, space, and laboratory environments. Many pieces of evidence for magnetic reconnection have been uncovered. However, its specific processes that could be…

Solar and Stellar Astrophysics · Physics 2018-10-24 X. Cheng , Y. Li , L. F. Wan , M. D. Ding , P. F. Chen , J. Zhang , J. J. Liu

Various astrophysical studies have motivated the investigation of the transport of high energy particles in magnetic turbulence, either in the source or en route to the observation sites. For strong turbulence and large rigidity, the…

High Energy Astrophysical Phenomena · Physics 2011-07-08 I. Plotnikov , G. Pelletier , M. Lemoine

We present a combined model for magnetic field generation and transport in cool stars with outer convection zones. The mean toroidal magnetic field, which is generated by a cyclic thin-layer alpha-omega dynamo at the bottom of the…

Solar and Stellar Astrophysics · Physics 2011-11-11 Emre Işık , Dieter Schmitt , Manfred Schüssler

The interplay between plasma turbulence and magnetic reconnection remains an unsettled question in astrophysical and laboratory plasmas. Here we report the first observational evidence that magnetic reconnection drives subion scale…

Plasma Physics · Physics 2023-05-31 Davide Manzini , Fouad Sahraoui , Francesco Califano

We summarize recent 2D MHD simulations of line-driven stellar winds from rotating hot-stars with a dipole magnetic field aligned to the star's rotation axis. For moderate to strong fields, much wind outflow is initially along closed…

Astrophysics · Physics 2007-05-23 Stan Owocki , Asif ud-Doula

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

Magnetic reconnection is commonly perceived to drive flow and particle acceleration in flares of solar, stellar, and astrophysical disk coronae but the relative roles of different acceleration mecha- nisms in a given reconnection…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Jared C. Workman , Eric G. Blackman , Chuang Ren

The gaseous media of galaxy clusters and cosmic filaments, which constitute most of the baryonic matter in the universe, is highly dynamic. It is also probably turbulent, although the turbulence properties are poorly known. The gas is…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 T. W. Jones , D. H. Porter , D. Ryu , J. Cho

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

Magnetic flux redistribution lies at the heart of the problem of star formation in dense cores of molecular clouds that are magnetized to a realistic level. If all of the magnetic flux of a typical core were to be dragged into the central…

Solar and Stellar Astrophysics · Physics 2015-06-05 Ruben Krasnopolsky , Zhi-Yun Li , Hsien Shang , Bo Zhao

We review recent advances in the numerical modeling of turbulent flows and star formation. An overview of the most widely used simulation codes and their core capabilities is provided. We then examine methods for achieving the…

Astrophysics of Galaxies · Physics 2026-04-22 Christoph Federrath , Stella Offner

The magnetic field of molecular clouds (MCs) plays an important role in the process of star formation: it determins the statistical properties of supersonic turbulence that controls the fragmentation of MCs, controls the angular momentum…

Astrophysics of Galaxies · Physics 2017-12-12 Paolo Padoan

Magnetic reconnection is a process that changes magnetic field topology in highly conducting fluids. Within the standard Sweet-Parker model, this process would be too slow to explain observations (e.g. solar flares). In reality, the process…

Astrophysics of Galaxies · Physics 2017-04-05 Grzegorz Kowal , Diego A. Falceta-Gonçalves , Alex Lazarian , Ethan T. Vishniac