Controlling the type and intensity of low-frequency waves generated by laser plasma clots in a force tube of magnetized plasma

Abstract In this work, we study the influence of the parameters of a magnetized background plasma on the intensity of whistler waves generated by periodic laser plasma bunches in a magnetic field tube. It is shown that at 0.3 < Lpi > 0.4 Alfvén waves and whistlers are generated. In the region Lpi> 0.5, intense whistlers with an amplitude of δBmax / B0 ∼ 0.24 are generated.

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Effect of thermal pressure on upward plasma fluxes due to ponderomotive force of Alfvén waves

Nonlinear Processes in Geophysics ◽

10.5194/npg-18-235-2011 ◽

2011 ◽

Vol 18 (2) ◽

pp. 235-241 ◽

Cited By ~ 5

Author(s):

A. K. Nekrasov ◽

F. Z. Feygin

Keyword(s):

Magnetic Moment ◽

Ponderomotive Force ◽

Standing Waves ◽

Low Frequency ◽

Alfven Waves ◽

Background Plasma ◽

Alfvén Waves ◽

Thermal Pressure ◽

Plasma Displacement

Abstract. We consider the action of the ponderomotive force of low-frequency Alfvén waves on the distribution of the background plasma. It is assumed that the ponderomotive force for traveling waves arises as a result of the background inhomogeneity of medium under study. Expressions for the ponderomotive force obtained in this paper differ from previous analogous results. The induced magnetic moment of medium is taken into account. It is shown that the well-known Pitayevsky's formula for the magnetic moment is not complete. The role of the induced nonlinear thermal pressure in the evolution of the background plasma is considered. We give estimations for plasma displacement due to the long- and short-acting nonlinear wave perturbations. Some discussion of the ponderomotive action of standing waves is provided.

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Alfvén waves in the foreshock propagating upstream in the plasma rest frame: statistics from Cluster observations

Annales Geophysicae ◽

10.5194/angeo-22-2315-2004 ◽

2004 ◽

Vol 22 (7) ◽

pp. 2315-2323 ◽

Cited By ~ 29

Author(s):

Y. Narita ◽

K.-H. Glassmeier ◽

S. Schäfer ◽

U. Motschmann ◽

M. Fränz ◽

...

Keyword(s):

Rest Frame ◽

Low Frequency ◽

Alfven Waves ◽

Alfvén Waves ◽

Phase Velocities ◽

Wave Numbers ◽

The Magnetic Field ◽

Proton Cyclotron ◽

Low Frequency Waves ◽

Alfven Velocity

Abstract. We statistically study various properties of low-frequency waves such as frequencies, wave numbers, phase velocities, and polarization in the plasma rest frame in the terrestrial foreshock. Using Cluster observations the wave telescope or k-filtering is applied to investigate wave numbers and rest frame frequencies. We find that most of the foreshock waves propagate upstream along the magnetic field at phase velocity close to the Alfvén velocity. We identify that frequencies are around 0.1xΩcp and wave numbers are around 0.1xΩcp/VA, where Ωcp is the proton cyclotron frequency and VA is the Alfvén velocity. Our results confirm the conclusions drawn from ISEE observations and strongly support the existence of Alfvén waves in the foreshock.

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Collisional instability in a rare magnetized plasma: an experimental model for magnetospheric and space plasma study

Journal of Plasma Physics ◽

10.1017/s0022377809007818 ◽

2009 ◽

Vol 75 (3) ◽

pp. 395-406 ◽

Cited By ~ 9

Author(s):

CONSTANTINE L. XAPLANTERIS

Keyword(s):

Magnetic Field ◽

Growth Rate ◽

Theoretical Model ◽

Low Frequency ◽

Space Plasma ◽

Magnetized Plasma ◽

Laboratory Plasma ◽

Geometrical Symmetry ◽

Low Frequency Waves ◽

Production Conditions

AbstractIn a suitable experimental device, laboratory plasma is produced with conditions and parameters analogous to magnetospheric plasma; we light a rare plasma in a semi-machine using rf-frequency discharge. Three ranges of low-frequency instabilities appear, one of which is identified as drift, caused by electron–neutral collisions. A full theoretical elaboration adapted to production conditions and geometrical symmetry is carried out; one solution of the dispersion relation is sufficient justification for the existence of the instability. The mathematical analysis also has the ambition to give interpretation for other low-frequency waves. Here we make a sound identification of the instability type as drift resistive due to electron–neutral collisions by an investigation of the growth rate. An agreement between experimental results and the theoretical model is obtained. As in the magnetosphere, an external magnetic field restrains the plasma.

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The parametric excitation of kinetic Alfvén waves by a magnetic pump

Journal of Plasma Physics ◽

10.1017/s0022377800010667 ◽

1981 ◽

Vol 26 (2) ◽

pp. 253-266 ◽

Cited By ~ 3

Author(s):

N. F. Cramer ◽

I. J. Donnelly

Keyword(s):

Finite Temperature ◽

Acoustic Waves ◽

Temperature Effects ◽

Mode Conversion ◽

Low Frequency ◽

Alfven Waves ◽

Alfven Wave ◽

Alfvén Waves ◽

Ion Acoustic Wave ◽

Low Frequency Waves

The parametric decay of a magneto-acoustic pump wave into low-frequency waves modified by finite temperature effects is considered. The excited waves are the kinetic Alfvén wave and the ion-acoustic wave. The former wave plays an important role in linear heating schemes employing the mode conversion of magneto-acoustic waves at the Alfvén resonance. Here we calculate the parametric growth rates and pump thresholds for excitation of these waves. The main result is that finite temperature effects tend to reduce the growth rate of Alfvén waves.

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Association of Alfvén waves and proton cyclotron waves with electrostatic bipolar pulses: magnetic hole events observed by Polar

Nonlinear Processes in Geophysics ◽

10.5194/npg-11-205-2004 ◽

2004 ◽

Vol 11 (2) ◽

pp. 205-213 ◽

Cited By ~ 6

Author(s):

G. S. Lakhina ◽

B. T. Tsurutani ◽

J. Pickett

Keyword(s):

Boundary Layer ◽

Free Energy ◽

High Frequency ◽

Low Frequency ◽

Alfven Waves ◽

Alfvén Waves ◽

Polar Cap ◽

Electron Holes ◽

Proton Cyclotron ◽

Low Frequency Waves

Abstract. Two magnetic hole events observed by Polar on 20 May 1996 when it was in the polar cap/polar cusp boundary layer are studied. Low-frequency waves, consisting of nonlinear Alfvén waves and large amplitude (±14nT peak-to-peak) obliquely propagating proton cyclotron waves (with frequency f~0.6 to 0.7 fcp), accompanied by electric bipolar pulses (electron holes) and electron heating have been observed located within magnetic holes. It is shown that low-frequency waves can provide free energy to drive some high frequency instabilities which saturate by trapping electrons, thus, leading to the generation of electron holes.

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Anisotropic model for resonant heating of ions by Alfvén waves

Journal of Plasma Physics ◽

10.1017/s0022377813000871 ◽

2013 ◽

Vol 79 (5) ◽

pp. 963-971 ◽

Cited By ~ 2

Author(s):

T. X. ZHANG

Keyword(s):

Magnetic Field ◽

Coronal Holes ◽

Alfven Waves ◽

Magnetized Plasma ◽

Alfven Wave ◽

Alfvén Waves ◽

Anisotropic Model ◽

Ion Cyclotron ◽

Heating Model ◽

Resonant Heating

AbstractAnisotropic heating of ions by Alfvén waves with frequency in the ion–cyclotron frequency range and propagation parallel to the magnetic field lines is investigated. First, particle–Alfvén wave interactions are quasilinearly examined from the kinetic theory in a hot multi-ion-magnetized plasma. As a result, the parallel and perpendicular heating rates of ions are derived analytically. Then, in terms of this anisotropic heating model and the dispersion relation of magnetic field-aligned left-hand polarized electromagnetic ion–cyclotron–Alfvén (EMICA) waves, the resonant heating of H, 2H, 3H, 3He, and 4He ions in a typical preheated laboratory plasma is numerically studied. It is shown that the EMICA waves can efficiently heat ions through cyclotron resonances primarily in the perpendicular direction. The perpendicular temperatures of H, 2H, 3H, 3He, and 4He increase much faster than the parallel ones. In comparison with the result from the previously developed isotropic heating model, the parallel heating by the EMICA waves is about much weaker, while the perpendicular heating is more efficient. Parameters such as density, temperature, magnetic field, wave-energy density, and ion species can affect the efficiency of the Alfvén wave heating in a similar way as shown in the isotropic heating model. The anisotropic model can be applied to explain the measurements of why O+5 and Mg+9 are heated extreme perpendicularly in solar coronal holes.

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PEMANFAATAN RADIASI ENERGI TEGANGAN 150 KV UNTUK LAMPU LED PENERANGAN JALAN

Jurnal Teknik ◽

10.31000/jt.v7i1.936 ◽

2018 ◽

Vol 7 (1) ◽

Author(s):

Mauludi Manfaluthy

Keyword(s):

Magnetic Field ◽

Electric Field ◽

High Voltage ◽

Low Frequency ◽

Energy Utilization ◽

World Health ◽

Electromagnetic Signals ◽

Health Organization ◽

The Magnetic Field ◽

Low Frequency Waves

WHO (World Health Organization) concludes that not much effect is caused by electric field up to 20 kV / m in humans. WHO standard also mentions that humans will not be affected by the magnetic field under 100 micro tesla and that the electric field will affect the human body with a maximum standard of 5,000 volts per meter. In this study did not discuss about the effect of high voltage radiation SUTT (High Voltage Air Channel) with human health. The research will focus on energy utilization of SUTT radiation. The combination of electric field and magnetic field on SUTT (70-150KV) can generate electromagnetic (EM) and radiation waves, which are expected to be converted to turn on street lights around the location of high voltage areas or into other forms. The design of this prototype works like an antenna in general that captures electromagnetic signals and converts them into AC waves. With a capacitor that can store the potential energy of AC and Schottky diode waves created specifically for low frequency waves, make the current into one direction (DC). From the research results obtained the current generated from the radiation is very small even though the voltage is big enough.Keywords : Radiance Energy, Joule Thief, and LED Module.

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Integral Equations for Problems on Wave Propagation in Near-Earth Plasma

Symmetry ◽

10.3390/sym13081395 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1395

Author(s):

Danila Kostarev ◽

Dmitri Klimushkin ◽

Pavel Mager

Keyword(s):

Magnetic Field ◽

Integral Equations ◽

Field Potential ◽

Low Frequency ◽

Fredholm Equation ◽

Compression Waves ◽

Parallel Component ◽

Electric Field Potential ◽

The Magnetic Field ◽

Low Frequency Waves

We consider the solutions of two integrodifferential equations in this work. These equations describe the ultra-low frequency waves in the dipol-like model of the magnetosphere in the gyrokinetic framework. The first one is reduced to the homogeneous, second kind Fredholm equation. This equation describes the structure of the parallel component of the magnetic field of drift-compression waves along the Earth’s magnetic field. The second equation is reduced to the inhomogeneous, second kind Fredholm equation. This equation describes the field-aligned structure of the parallel electric field potential of Alfvén waves. Both integral equations are solved numerically.

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