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Related papers: Fluctuation dynamo based on magnetic reconnections

200 papers

A magnetic flux tube may be considered both as a separate body and as a confined field. As a field, it is affected both by differential rotation ($\Omega$-effect) and cyclonic convection ($\alpha$-effect). As a body, the tube experiences…

Astrophysics · Physics 2009-11-13 L. H. Li , S. Sofia , G. Belvedere

Context. Solar activity cycles vary in amplitude and duration. The variations can be at least partly explained by fluctuations in dynamo parameters. Aims. We want to restrict uncertainty in fluctuating dynamo parameters and find out which…

Solar and Stellar Astrophysics · Physics 2018-07-18 L. L. Kitchatinov , A. V. Mordvinov , A. A. Nepomnyashchikh

We argue that the recently reported Kolmogorov-like magnetic turbulence spectrum in the cool core of the Hydra A galaxy cluster can be understood by kinetic energy injection by active galaxies that drives a turbulent non-helical magnetic…

Astrophysics · Physics 2009-11-11 T. A. Ensslin , C. Vogt

Suppression of fluctuations of normally perturbed magnetic fields in dynamo waves and slow dynamos along curved (folded), torsioned (twisted) and non-stretched, diffusive filaments are obtained. This form of fluctuations suppression has…

Astrophysics · Physics 2008-06-24 L. C. Garcia de Andrade

We present an analysis of the formation of atmospheric flux ropes in a magnetohydrodynamic (MHD) solar flux emergence simulation. The simulation domain ranges from the top of the solar interior to the low corona. A twisted magnetic flux…

Solar and Stellar Astrophysics · Physics 2015-06-17 David MacTaggart , Andrew Haynes

In a collisionless, magnetized plasma, particles may stream freely along magnetic-field lines, leading to phase "mixing" of their distribution function and consequently to smoothing out of any "compressive" fluctuations (of density,…

Plasma Physics · Physics 2019-03-27 Romain Meyrand , Anjor Kanekar , William Dorland , Alexander A. Schekochihin

Formed through magnetic field shearing and reconnection in the solar corona, magnetic flux ropes are structures of twisted magnetic field, threaded along an axis. Their evolution and potential eruption are of great importance for space…

Solar and Stellar Astrophysics · Physics 2017-09-13 Chris Lowder , Anthony Yeates

Remote and in-situ observations strongly imply that the slow solar wind consists of plasma from the hot, closed-field corona that is released onto open magnetic field lines. The Separatrix Web (S-Web) theory for the slow wind proposes that…

Solar and Stellar Astrophysics · Physics 2017-05-26 A. K. Higginson , S. K. Antiochos , C. R. DeVore , P. F. Wyper , T. H. Zurbuchen

Disconnection of open magnetic flux by reconnection is required to balance the injection of open flux by CMEs and other eruptive events. Making use of recent advances in heliospheric background subtraction, we have imaged many abrupt…

Solar and Stellar Astrophysics · Physics 2015-06-03 C. E. DeForest , T. A. Howard , D. J. McComas

Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since…

Solar and Stellar Astrophysics · Physics 2018-02-14 Kalman J. Knizhnik , Vadim M. Uritsky , James A. Klimchuk , C. Richard DeVore

We report the results of a magneto-hydrodynamic (MHD) simulation of a convective dynamo in a model solar convective envelope driven by the solar radiative diffusive heat flux. The convective dynamo produces a large-scale mean magnetic field…

Solar and Stellar Astrophysics · Physics 2014-06-18 Yuhong Fan , Fang Fang

Magnetic reconnection, the rearrangement of magnetic field topology, is a fundamental physical process in magnetized plasma systems all over the universe1,2. Its process is difficult to be directly observed. Coronal structures, such as…

Solar and Stellar Astrophysics · Physics 2016-09-21 Leping Li , Jun Zhang , Hardi Peter , Eric Priest , Huadong Chen , Lijia Guo , Feng Chen , Duncan Mackay

Using fully kinetic 3D simulations, the reconnection dynamics of asymmetric current sheets are examined at the Earth's magnetopause. The plasma parameters are selected to model MMS magnetopause diffusion region crossings with guide fields…

Recent data on superflares on sun-like stars and radiocarbon data on solar activity in the past are both indicative of transient epochs of unusually high magnetic activity. We propose an explanation for the grand activity maxima in the…

Solar and Stellar Astrophysics · Physics 2016-05-05 L. L. Kitchatinov , S. V. Olemskoy

The violent disruption of the coronal magnetic field is often observed to be restricted to the low corona, appearing as a confined eruption. The possible causes of the confinement remain elusive. Here, we model the eruption of a magnetic…

Solar and Stellar Astrophysics · Physics 2023-07-19 Jun Chen , Xin Cheng , Bernhard Kliem , Mingde Ding

We explore the suggestions by Uzdensky (2007) and Cassak et al. (2008) that coronal loops heated by magnetic reconnection should self-organize to a state of marginal collisionality. We discuss their model of coronal loop dynamics with a…

Solar and Stellar Astrophysics · Physics 2015-06-05 S. Imada , E. G. Zweibel

The role of turbulence in current generation and self-excitation of magnetic fields has been studied in the geometry of a mechanically driven, spherical dynamo experiment, using a three dimensional numerical computation. A simple impeller…

Plasma Physics · Physics 2009-11-11 R. A. Bayliss , C. B. Forest , M. D. Nornberg , E. J. Spence , P. W. Terry

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

We present a model for magnetic energy dissipation in a pulsar wind nebula. Better understanding of this process is required to assess the likelihood that certain astrophysical transients may be powered by the spin-down of a "millisecond…

High Energy Astrophysical Phenomena · Physics 2017-09-27 Jonathan Zrake , Jonathan Arons

Recent observations suggest that magnetic flux cancellation may play a crucial role in heating the Sun's upper atmosphere (chromosphere, transition region, corona). Here, we intended to validate an analytic model for magnetic reconnection…

Solar and Stellar Astrophysics · Physics 2020-07-08 Sung-Hong Park