The Three-dimensional Structure of a Sunspot Magnetic Field

Reduced, approximate MHD equations are derived for the case where the magnetic field is close to a potential field. The potential field can have an arbitrary three-dimensional structure, as long as it is non-vanishing. Finite current and pressure effects are included.

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Three-dimensional structure of the magnetic field in the disk of the Milky Way

Astronomy and Astrophysics ◽

10.1051/0004-6361/201730740 ◽

2017 ◽

Vol 603 ◽

pp. A15 ◽

Cited By ~ 8

Author(s):

A. Ordog ◽

J. C. Brown ◽

R. Kothes ◽

T. L. Landecker

Keyword(s):

Magnetic Field ◽

Milky Way ◽

Three Dimensional ◽

Dimensional Structure ◽

Three Dimensional Structure ◽

The Magnetic Field

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Three-dimensional density and compressible magnetic structure in solar wind turbulence

Annales Geophysicae ◽

10.5194/angeo-36-527-2018 ◽

2018 ◽

Vol 36 (2) ◽

pp. 527-539 ◽

Cited By ~ 6

Author(s):

Owen W. Roberts ◽

Yasuhito Narita ◽

C.-Philippe Escoubet

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Three Dimensional ◽

Field Direction ◽

Dimensional Structure ◽

Magnetic Field Direction ◽

Three Dimensional Structure ◽

Slow Wind ◽

Incompressible Turbulence ◽

The Magnetic Field

Abstract. The three-dimensional structure of both compressible and incompressible components of turbulence is investigated at proton characteristic scales in the solar wind. Measurements of the three-dimensional structure are typically difficult, since the majority of measurements are performed by a single spacecraft. However, the Cluster mission consisting of four spacecraft in a tetrahedral formation allows for a fully three-dimensional investigation of turbulence. Incompressible turbulence is investigated by using the three vector components of the magnetic field. Meanwhile compressible turbulence is investigated by considering the magnitude of the magnetic field as a proxy for the compressible fluctuations and electron density data deduced from spacecraft potential. Application of the multi-point signal resonator technique to intervals of fast and slow wind shows that both compressible and incompressible turbulence are anisotropic with respect to the mean magnetic field direction P⟂≫P∥ and are sensitive to the value of the plasma beta (β; ratio of thermal to magnetic pressure) and the wind type. Moreover, the incompressible fluctuations of the fast and slow solar wind are revealed to be different with enhancements along the background magnetic field direction present in the fast wind intervals. The differences in the fast and slow wind and the implications for the presence of different wave modes in the plasma are discussed. Keywords. Interplanetary physics (MHD waves and turbulence)

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Study of Three-Dimensional Polishing Using Magnetic Compound Fluid (MCF)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.76-78.288 ◽

2009 ◽

Vol 76-78 ◽

pp. 288-293 ◽

Cited By ~ 3

Author(s):

Takashi Sato ◽

Yong Bo Wu ◽

Wei Min Lin ◽

Kunio Shimada

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Permanent Magnet ◽

Static Magnetic Field ◽

Magnetic Particles ◽

Three Dimensional ◽

Dimensional Structure ◽

Flexible Tool ◽

Three Dimensional Structure ◽

Polishing Force

Magnetic compound fluid (MCF), a functional fluid responding to magnetic field, is expected for an application to many engineering fields. In this paper, the effect of magnetic fields on the polishing force and the restoring ability of the MCF are studied followed by the proposal of a new polishing technique using the MCF. Under a fluctuating magnetic field generated by a revolution of permanent magnet, the magnetic particles in the MCF show a higher particle disposition and an accumulating action compared to a static magnetic field. Thus the MCF generates the greater restoring ability but the lower polishing force compared to that under the static magnetic field. When the MCF under the fluctuating magnetic field is applied to the polishing as the flexible tool, it shows the high polishing performance. As a result, a feasibility of a new polishing technique using the MCF for a three-dimensional structure is confirmed.

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