Light transmission, magnetodielectric and magnetoresistive effects in membranes based on hybrid magnetorheological suspensions in a static magnetic field superimposed on a low/medium frequency electric field

Abstract. Electron beams narrowly collimated to the magnetic field line were observed continuously from a down-ward current region to an auroral acceleration region (i.e., upward current region). They were well correlated with low-frequency electric field fluctuations in the auroral acceleration region as well as in the adjacent downward current region. Magnetic field fluctuations were found only in the downward current region. The analysis suggests that static field-aligned electric fields are not fully responsible for the filed-aligned electron acceleration; the ac electric field, presumably associated with Alfvenic fluctuations, should also be involved in the acceleration of ionospheric electrons.Key words. Ionosphere (particle acceleration) – Magnetospheric physics (auroral phenomena; magnetosphere-ionosphere interactions)

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Magneto-electrical orientation of lipid-coated graphitic micro-particles in solution

RSC Advances ◽

10.1039/c6ra07657b ◽

2016 ◽

Vol 6 (52) ◽

pp. 46643-46653 ◽

Cited By ~ 4

Author(s):

Johnny Nguyen ◽

Sonia Contera ◽

Isabel Llorente García

Keyword(s):

Magnetic Field ◽

Electric Field ◽

Static Magnetic Field ◽

Time Varying ◽

Micro Particles ◽

First Time

We demonstrate, for the first time, confinement of the orientation of graphitic micro-flakes to a well-defined plane in solution by applying two perpendicular fields: a vertical static magnetic field and a horizontal time-varying electric field.

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FRB coherent emission from decay of Alfvén waves

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa774 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2385-2395 ◽

Cited By ~ 10

Author(s):

Pawan Kumar ◽

Željka Bošnjak

Keyword(s):

Magnetic Field ◽

Wave Packet ◽

Electric Field ◽

Static Magnetic Field ◽

Strong Electric Field ◽

Alfven Waves ◽

Alfven Wave ◽

Alfvén Waves ◽

Radio Waves ◽

Electron Positron

ABSTRACT We present a model for fast radio bursts (FRBs) where a large-amplitude Alfvén wave packet is launched by a disturbance near the surface of a magnetar, and a substantial fraction of the wave energy is converted to coherent radio waves at a distance of a few tens of neutron star radii. The wave amplitude at the magnetar surface should be about 1011 G in order to produce an FRB of isotropic luminosity 1044 erg s−1. An electric current along the static magnetic field is required by Alfvén waves with non-zero component of transverse wave vector. The current is supplied by counter-streaming electron–positron pairs, which have to move at nearly the speed of light at larger radii as the plasma density decreases with distance from the magnetar surface. The counter-streaming pairs are subject to two-stream instability, which leads to formation of particle bunches of size of the order of c/ωp, where ωp is the plasma frequency. A strong electric field develops along the static magnetic field when the wave packet arrives at a radius where electron–positron density is insufficient to supply the current required by the wave. The electric field accelerates particle bunches along the curved magnetic field lines, and that produces the coherent FRB radiation. We provide a number of predictions of this model.

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