The Doppler-shifted cyclotron resonance −kzvz= f between fast ions and shear Alfvén waves is experimentally investigated , wave frequency; kz, axial wavenumber; vz, fast-ion axial speed; f, fast-ion cyclotron frequency . A test particle beam of fast ions is launched by a Li+ source in the helium plasma of the LArge Plasma Device LAPD W. Gekelman, H. Pfister, Z. Lucky, J. Bamber, D. Leneman, and...

The dispersion equation is analyzed for waves in a strongly magnetized, electron-positron plasma in which counterstreaming electrons are cold in their respective rest frames. For propagation parallel to the magnetic field the dispersion equation factorizes into equations for two longitudinal modes and four transverse modes. Instabilities occur in both longitudinal and transverse modes, with the...

Density irregularities near the plasmapause are commonly observed and play an important role in whistler-mode wave excitation propagation. In this study, we report a frequency-dependent modulation event of waves by background density during geomagnetic storm. Higher-frequency whistler (near , where is equatorial electron cyclotron frequency) trapped trough regions due to small refractive index ...

Terahertz (THz) radiation can revolutionize modern science and technology. To this date, it remains big challenges to develop intense, coherent and tunable THz radiation sources that can cover the whole THz frequency region either by means of only electronics (both vacuum electronics and semiconductor electronics) or of only photonics (lasers, for example, quantum cascade laser). Here we presen...

LFEW is a low frequency electromagnetic wave detector mounted on TC-2, which can measure the magnetic fluctuation of low frequency electromagnetic waves. The frequency range is 8 Hz to 10 kHz. LFEW comprises a boommounted, three-axis search coil magnetometer, a preamplifier and an electronics box that houses a Digital Spectrum Analyzer. LFEW was calibrated at Chambon-la-Forêt in France. The gro...

Fourier transform ion cyclotron resonance mass spectrometry is based on image current detection of coherently excited ion cyclotron motion. The detected signal magnitude and peak shape may be understood from idealized behavior: single ion, zero-pressure, spatially uniform magnetic field, three-dimensional axial quadrupolar electrostatic trapping potential, and spatially uniform resonant alterna...

We report on the impulsive excitation and control of intersubband and hybrid intersubband-cyclotron modes in a twodimensional electron gas by ultrafast optical pulses. Pump-probe experiments were performed in the reflection geometry on a modulation-doped GaAs/AlxGa1KxAs quantum well at 7 K. Using a pulse shaper to produce multiple excitation pulses, we demonstrate coherent control of charge-den...

A ®lter method is presented which allows a qualitative and quantitative identi®cation of wave modes observed with plasma experiments on satellites. Hitherto existing mode ®lters are based on the MHD theory and thus they are restricted to low frequencies well below the ion cyclotron frequency. The present method is generalized to cover wave modes up to the characteristic ion frequencies. The spe...

In this paper, ion cyclotron emissions (ICEs) due to deuterium-deuterium (DD) fusion-product (FP) He, T and P-ions on JT-60U are described. Electromagnetic waves with finite toroidal wave numbers are detected by using ion cyclotron range of frequency antennas as pickup loops. The toroidal wave numbers are evaluated from the phase differences between two antenna straps arrayed in the toroidal di...

The fast solar wind’s high speeds and non-thermal features require that considerable heating occurs well above the Sun’s surface. Two leading theories seem incompatible: low-frequency ‘Alfvénic’ turbulence, which transports energy outwards is observed ubiquitously by spacecraft but seems insufficient to explain dominance of ion over electron heating; high-frequency ion-cyclotron waves, ions lac...