Asymmetry in the electric and magnetic field polarization of geomagnetic pulsations

For understanding the effect of resonant helical magnetic field (RHF) and bias on the edge plasma turbulent transport, the radial and poloidal electric field (Er, EP), poloidal and toroidal magnetic field (BP, Br) were detected by the Langmuir probe, magnetic probe and diamagnetic loop. The poloidal, toroidal and radial velocity (VP, Vr, Vt) can be determined from the electric and magnetic field. In the present work, we have investigated the effect of the magnitude of bias (Vbias = 200v, Vbias = 320v) on Er, EP, BP, Bt, VP, Vr, Vt. Moreover, we applied RHF with L = 2, L = 3 and L = 2 and 3 and investigate the effect of the helical windings radius on above parameters. Also, the experiment was repeated by applying the positive biasing potentials and RHF's simultaneously. The results show that by applying bias to the plasma at t = 15 msec at r/a = 0.9, Er, BP and Bt increase while EP decreases. The best modification occurs at Vbias = 200v. By applying RHF to the plasma, both the electric and magnetic field vary. Er reaches the highest in the presence of RHF with L = 3. The same results are obtained for BP, Bt, VP and Vt. While the inverse results are obtained for EP and Vr. Finally, RHF and bias are applied simultaneously to the plasma. With applied bias with Vbias = 200v and RHF with L = 2 and 3, we reach to the ideal circumstance. The same results obtain in the situation with Vbias = 320v and RHF with L = 2 and 3.

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Electric and magnetic field dependence of the conductivity in poly(3-hexylthiophene langmuir-blodgett films

Synthetic Metals ◽

10.1016/0379-6779(93)90852-n ◽

1993 ◽

Vol 57 (2-3) ◽

pp. 4997-5002 ◽

Cited By ~ 1

Author(s):

E. Punkka ◽

M.F. Rubner ◽

J.D. Hettinger ◽

J.S. Brooks ◽

S.T. Hannahs

Keyword(s):

Magnetic Field ◽

Field Dependence ◽

Magnetic Field Dependence ◽

Langmuir Blodgett ◽

Electric And Magnetic Field ◽

Langmuir Blodgett Films

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Different permeabilization patterns of splenocytes and thymocytes to combination of pulsed electric and magnetic field treatments

Bioelectrochemistry ◽

10.1016/j.bioelechem.2018.04.006 ◽

2018 ◽

Vol 122 ◽

pp. 183-190 ◽

Cited By ~ 3

Author(s):

Vitalij Novickij ◽

Auksė Zinkevičienė ◽

Justinas Valiulis ◽

Jurgita Švedienė ◽

Algimantas Paškevičius ◽

...

Keyword(s):

Magnetic Field ◽

Electric And Magnetic Field

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Influence of high-latitude geomagnetic pulsations on recordings of broadband force-balanced seismic sensors

Geoscientific Instrumentation Methods and Data Systems ◽

10.5194/gi-1-85-2012 ◽

2012 ◽

Vol 1 (2) ◽

pp. 85-101 ◽

Cited By ~ 2

Author(s):

E. Kozlovskaya ◽

A. Kozlovsky

Keyword(s):

Magnetic Field ◽

Geomagnetic Field ◽

Geomagnetic Latitude ◽

Low Frequency ◽

Auroral Oval ◽

Polar Regions ◽

Geomagnetic Pulsations ◽

Seismic Sensors ◽

Magnetic Poles ◽

Magnetic Disturbances

Abstract. Seismic broadband sensors with electromagnetic feedback are sensitive to variations of surrounding magnetic field, including variations of geomagnetic field. Usually, the influence of the geomagnetic field on recordings of such seismometers is ignored. It might be justified for seismic observations at middle and low latitudes. The problem is of high importance, however, for observations in Polar Regions (above 60° geomagnetic latitude), where magnitudes of natural magnetic disturbances may be two or even three orders larger. In our study we investigate the effect of ultra-low frequency (ULF) magnetic disturbances, known as geomagnetic pulsations, on the STS-2 seismic broadband sensors. The pulsations have their sources and, respectively, maximal amplitudes in the region of the auroral ovals, which surround the magnetic poles in both hemispheres at geomagnetic latitude (GMLAT) between 60° and 80°. To investigate sensitivity of the STS-2 seismometer to geomagnetic pulsations, we compared the recordings of permanent seismic stations in northern Finland to the data of the magnetometers of the IMAGE network located in the same area. Our results show that temporary variations of magnetic field with periods of 40–150 s corresponding to regular Pc4 and irregular Pi2 pulsations are seen very well in recordings of the STS-2 seismometers. Therefore, these pulsations may create a serious problem for interpretation of seismic observations in the vicinity of the auroral oval. Moreover, the shape of Pi2 magnetic disturbances and their periods resemble the waveforms of glacial seismic events reported originally by Ekström (2003). The problem may be treated, however, if combined analysis of recordings of co-located seismic and magnetic instruments is used.

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