Equilibrium States of an Elastic Conductor in a Magnetic Field: A Paradigm of Bifurcation Theory

A brief critique is presented of some different classes of magnetohydrodynamic equilibrium solutions based on their continuity properties and whether the magnetic field is integrable or not. A generalized energy functional is introduced that is comprised of alternating ideal regions, with nested flux surfaces with an irrational rotational transform, and Taylor-relaxed regions, possibly with magnetic islands and chaos. The equilibrium states have globally continuous magnetic fields, and may be constructed for arbitrary three-dimensional plasma boundaries and appropriately prescribed pressure and rotational-transform profiles.

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Мультистабильность дипольной наноячейки при ее импульсном перемагничивании

Физика твердого тела ◽

10.21883/ftt.2020.10.49914.104 ◽

2020 ◽

Vol 62 (10) ◽

pp. 1647

Author(s):

А.М. Шутый ◽

Д.И. Семенцов

Keyword(s):

Magnetic Field ◽

Magnetic Moment ◽

Equilibrium States ◽

Gaussian Pulse ◽

Mutual Orientation ◽

Magnetic Reversal ◽

Final State ◽

Original Configuration

Dynamics of pulse magnetic reversal of nanocell, composed of two magneto-one-axis nanoparticles, by short Gaussian pulse of magnetic field, was investigated. Such a dipole-bound system is multi-stable and has four equilibrium states. The conditions under which the nanocell is re-magnetized into one of three states or returned to the original configuration are revealed. It was shown that the nature of precession dynamics of magnetic moment and the choice of the final state of the nanocell depend on the amplitude and duration of the pulse, as well as on the mutual orientation of the light axes.

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Magnetic-field strengths from optical polarization data

Symposium - International Astronomical Union ◽

10.1017/s0074180900101263 ◽

1967 ◽

Vol 31 ◽

pp. 381-383

Author(s):

J. M. Greenberg

Keyword(s):

Magnetic Field ◽

Optical Polarization ◽

Polarization Data ◽

Term Model ◽

Source Of Information ◽

Field Strengths

Van de Hulst (Paper 64, Table 1) has marked optical polarization as a questionable or marginal source of information concerning magnetic field strengths. Rather than arguing about this–I should rate this method asq+-, or quarrelling about the term ‘model-sensitive results’, I wish to stress the historical point that as recently as two years ago there were still some who questioned that optical polarization was definitely due to magnetically-oriented interstellar particles.

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Observing the galactic magnetic field

Symposium - International Astronomical Union ◽

10.1017/s0074180900101251 ◽

1967 ◽

Vol 31 ◽

pp. 375-380

Author(s):

H. C. van de Hulst

Keyword(s):

Magnetic Field ◽

Fair Agreement ◽

Solar Neighbourhood ◽

Galactic Magnetic Field ◽

The Magnetic Field

Various methods of observing the galactic magnetic field are reviewed, and their results summarized. There is fair agreement about the direction of the magnetic field in the solar neighbourhood:l= 50° to 80°; the strength of the field in the disk is of the order of 10-5gauss.

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Structure in the radiation of the galactic disk

Symposium - International Astronomical Union ◽

10.1017/s0074180900101184 ◽

1967 ◽

Vol 31 ◽

pp. 355-356

Author(s):

R. D. Davies

Keyword(s):

Magnetic Field ◽

Galactic Disk ◽

Galactic Magnetic Field ◽

Measured Polarization

Observations at various frequencies between 136 and 1400 MHz indicate a considerable amount of structure in the galactic disk. This result appears consistent both with measured polarization percentages and with considerations of the strength of the galactic magnetic field.

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