Results 171 to 180 of about 26,415 (203)

ULF waves—A historical note

2006
The field of ultra-low frequency (ULF) wave research is an important piece in the jigsaw of the dynamics of the Earth's magnetospheric system. These waves are recognized through their interactions with particles and fields, and energy transfer processes.
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ULF waves and the ground magnetic field

Journal of Geophysical Research: Space Physics, 1998
A theory is put forward to account for the horizontal structure and polarization of the magnetic field of low‐frequency ULF waves on the ground at low latitudes. The theory is based on the condition that the component of the rotation of magnetic field normal to the Earth's surface vanishes in the neutral atmosphere and also on an assumption that the ...
M. Itonaga, K. Yumoto
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ULF Waves and Auroral Electrons

2006
The availability of high time resolution field and particle measurements from spacecraft has allowed a clear association between ULF waves and field-aligned electron acceleration on auroral field-lines to be established. We review the basic physics responsible for electron acceleration in Alfven waves and demonstrate using observations from the FAST ...
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Large-amplitude ULF waves at high latitudes

Journal of Atmospheric and Solar-Terrestrial Physics, 2014
Abstract We present results from the statistical study of ULF waves detected by the fluxgate magnetometer in Gakona, Alaska during several experimental campaigns conducted at the High Frequency Active Auroral Research Program (HAARP) facility in years 2011–2013.
T. Guido, B. Tulegenov, A.V. Streltsov
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ULF wave studies using ground-based arrays

Advances in Space Research, 1988
Abstract The presence of ULF plasma waves in the Earth's magnetosphere can be detected by using a wide variety of instruments on the Earth's surface, including all-sky imagers, ionospheric radar systems, riometers, magnetometers, and tellurics. Arrays of these instruments, particularly magnetometers, give relatively simple but effective systems for ...
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ULF Wave Eigenfrequencies in the Earth's Magnetosphere

2020
This thesis studies standing ultralow frequency (ULF) waves in the Earth's magnetosphere. In particular, it looks at how to automate the measurement of the resonant frequencies of geomagnetic field lines and how we can use this information to understand the driving processes.
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ULF wave investigations in the dayside cusp

Advances in Space Research, 1985
Analyse des micropulsations (IPCL, IPRP, Pc 1 et 2, Pc 3) observees dans la zone du cornet, cote jour. On recherche leurs mecanismes d'excitation, leurs origines et leurs relations avec les parametres du vent ...
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Digital techniques for ULF wave polarization analysis

Annales des Télécommunications, 1979
Digital power spectral and wave polarization analysis are powerful techniques for studying ULF waves in the earth's magnetosphere. Four different techniques for using the spectral matrix to perform such an analysis have been presented in the literature.
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Multi-satellite observations of ULF waves

2006
Single spacecraft observations of ULF waves can only give limited information on the properties of these waves. One can determine e.g., polarization and use minimum variance analysis to obtain an indication of the propagation direction. To obtain more and more accurate information, it is necessary to use multi-spacecraft data.
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ULF waves in the Magnetosphere

2007
Geomagnetic pulsations are the ground manifestation of ultra low frequency hydromagnetic waves propagating in the magnetosphere. Frequencies typically range between f  mHz and f  Hz; ground amplitudes range from less than . nT to tens or hundreds of nT and generally increase with latitude up to auroral/cusp regions.
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