Magnetic field structures inside magnetars with strong toroidal field

AbstractWe have analyzed the magnetized equilibrium studies with strong toroidal magnetic fields and found that the negative toroidal current density inside the star is very important for the strong toroidal magnetic fields. The strong toroidal magnetic fields require the strong poloidal current, but the strong poloidal current results in the localized strong toroidal current density in the axisymmetric system. This localized toroidal current changes the magnetic field configuration and makes the size of the toroidal magnetic field region smaller. As a result, the toroidal magnetic field energy can not become large. We need to cancel out the localized toroidal current density in order to obtain the large toroidal fields solutions. We have found and showed that the negative toroidal current cancels out the localized toroidal current density and sustain the large toroidal magnetic field energy inside the star. We can explain the magnetized equilibrium studies with strong toroidal magnetic fields systematically using the negative current density. Physical meaning of the negative current is key to the magnetar interior magnetic fields.

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Toroidal magnetic field configuration produced by multiply linked cusp magnetic fields.

Kakuyūgō kenkyū ◽

10.1585/jspf1958.51.57 ◽

1984 ◽

Vol 51 (1) ◽

pp. 57-68

Author(s):

Tsuguhiro Watanabe ◽

Satoshi Sugano ◽

Kiyotaka Hamamatsu

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Field Configuration ◽

Toroidal Magnetic Field ◽

Magnetic Field Configuration

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Direct transformation of magnetic-field energy into energy of fast particles

Symposium - International Astronomical Union ◽

10.1017/s007418090010083x ◽

1967 ◽

Vol 31 ◽

pp. 133-134

Author(s):

S. I. Syrovatskii

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Field Energy ◽

Direct Transformation ◽

Magnetic Field Energy ◽

Strongly Connected

There are two distinct but as it seems strongly connected problems. The first is the surprisingly rapid dissipation of magnetic fields which is observed in the Sun's atmosphere and must be supposed for some other objects as well. The second problem is the acceleration of fast particles in magnetized cosmical plasma.

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An Analytical Solution of the Problem of Plasma Ejection from the Magnetosphere of an Axisymmetric Rotator

International Astronomical Union Colloquium ◽

10.1017/s000273160015526x ◽

1992 ◽

Vol 128 ◽

pp. 245-247

Author(s):

S. V. Bogovalov

Keyword(s):

Magnetic Field ◽

Neutron Star ◽

Analytical Solution ◽

Toroidal Magnetic Field ◽

Field Energy ◽

Crab Pulsar ◽

Plasma Energy ◽

Light Cylinder ◽

Magnetic Field Energy

AbstractThe flow of e+e− plasma ejected by an axisymmetrically rotating magnetized neutron star is considered in a hydrodynamical approximation. It is shown that in the vicinity of the light cylinder a helical discontinuity is formed. The transformation of toroidal magnetic field energy into plasma energy takes place at this discontinuity. Particles are accelerated to an energy of 10TeV for a neutron star with the characteristics of the Crab pulsar.

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Axisymmetric and stationary magnetic field structures in neutron star crusts under various boundary conditions

Proceedings of the International Astronomical Union ◽

10.1017/s174392131400266x ◽

2013 ◽

Vol 9 (S302) ◽

pp. 427-428

Author(s):

Kotaro Fujisawa ◽

Shota Kisaka

Keyword(s):

Magnetic Field ◽

Neutron Star ◽

Magnetic Fields ◽

Boundary Conditions ◽

Outer Boundary ◽

Energy Ratio ◽

Field Energy ◽

Various Boundary Conditions ◽

The Core ◽

Magnetic Field Energy

AbstractWe have calculated many Hall equilibrium states within the neutron star crust under various boundary conditions in order to investigate the influences of the boundary conditions clearly. We have found two important features of these solutions. First, the magnitude of the core magnetic fields affects the toroidal to total magnetic field energy ratio within the crust (Et/E). If the core magnetic fields are vanished, the crustal toroidal magnetic fields become weak and the typical energy ratio is only Et / E ~ 0.1%. If the core magnetic fields are strong, however, the crustal toroidal magnetic fields become strong and the typical ratio reaches Et / E ~ 15%. Second, the core toroidal magnetic fields and the twisted magnetosphere around the star make the size of the crustal toroidal magnetic field regions large. Therefore if the strong core magnetic fields have strong toroidal component, both strength and size of the crustal toroidal magnetic fields become large. These results show that the Hall MHD evolutions would be deeply affected by both inner and outer boundary conditions.

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Experimental study of force-free, collinear plasma structures

Journal of Plasma Physics ◽

10.1017/s0022377800007285 ◽

1973 ◽

Vol 9 (1) ◽

pp. 1-15 ◽

Cited By ~ 20

Author(s):

E. E. Nolting ◽

P. E. Jindra ◽

D. R. Wells

Keyword(s):

Magnetic Field ◽

Experimental Study ◽

Magnetic Fields ◽

Flow Fields ◽

Diagnostic Techniques ◽

Field Configuration ◽

Magnetic Mirror ◽

Magnetic Field Configuration ◽

Magnetic Barrier ◽

Magnetic Well

Detailed measurements of the trapped magnetic fields and currents in plasma structures generated by conical theta-pinches are reported. Studies of these structures interacting with a magnetic barrier, and with each other in a collision at the centre of a magnetic mirror, are reported. The magnetic well formed by the collision has been studied by simultaneous use of several diagnostic techniques. The measurements are in agreement with a force-free, collinear magnetic field configuration (Wells 1972). Arguments relating superposability and collinearity of flow fields to these observations are given.

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The growth of magnetic field energy in conducting fluids

Computational Fluid and Solid Mechanics 2003 ◽

10.1016/b978-008044046-0.50245-1 ◽

2003 ◽

pp. 1004-1007

Author(s):

Philip Livermore ◽

Andrew Jackson

Keyword(s):

Magnetic Field ◽

Field Energy ◽

Magnetic Field Energy ◽

Conducting Fluids

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Mid-infrared Observations of Magnetic Fields in the Disks of Bi-Polar Outflow Sources

International Astronomical Union Colloquium ◽

10.1017/s0252921100044067 ◽

1997 ◽

Vol 163 ◽

pp. 799-800

Author(s):

Craig H. Smith ◽

Christopher M. Wright ◽

David K. Aitken ◽

Patrick F. Roche

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Field Configuration ◽

Field Direction ◽

Magnetic Field Direction ◽

Poloidal Field ◽

Mid Infrared ◽

Infrared Observations ◽

Polarization Mechanism ◽

The Magnetic Field

AbstractWe present the results from mid-infrared spectro-polarimetric observations of a number of bi-polar outflow sources. The specto-polarimetric data provides information on the polarization mechanism and the magnetic field direction. The field direction in the disks of the observed sources is most often normal to the ambient field direction and lies in the plane of the disk, indicating a toroidal rather than poloidal field configuration.

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Small, modular and economically attractive fusion enabled by high temperature superconductors

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2018.0354 ◽

2019 ◽

Vol 377 (2141) ◽

pp. 20180354 ◽

Cited By ~ 4

Author(s):

Dennis Whyte

Keyword(s):

Magnetic Field ◽

High Temperature ◽

Magnetic Fields ◽

Current Density ◽

High Temperature Superconductors ◽

Fusion Energy ◽

High Magnetic Fields ◽

Operating Temperatures ◽

The Magnetic Field ◽

Game Changer

The advantages of high magnetic fields in tokamaks are reviewed, and why they are important in leading to more compact tokamaks. A brief explanation is given of what limits the magnetic field in a tokamak, and why high temperature superconductors (HTSs) are a game changer, not just because of their higher magnetic fields but also for reasons of higher current density and higher operating temperatures. An accelerated pathway to fusion energy is described, defined by the SPARC and ARC tokamak designs. This article is part of a discussion meeting issue ‘Fusion energy using tokamaks: can development be accelerated?’.

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