Terrestrial VLF transmitter injection into the magnetosphere
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In this paper, an empirical measurement of the radiated power into the magnetosphere from ground-based very low frequency (VLF) transmitters is presented, for both daytime and nighttime, and at both the overhead and geomagnetic conjugate region.Abstract:
[1] Very Low Frequency (VLF, 3–30 kHz) radio waves emitted from ground sources (transmitters and lightning) strongly impact the radiation belts, driving electron precipitation via whistler-electron gyroresonance, and contributing to the formation of the slot region. However, calculations of the global impacts of VLF waves are based on models of trans-ionospheric propagation to calculate the VLF energy reaching the magnetosphere. Limited comparisons of these models to individual satellite passes have found that the models may significantly (by >20 dB) overestimate amplitudes of ground based VLF transmitters in the magnetosphere. To form a much more complete empirical picture of VLF transmitter energy reaching the magnetosphere, we present observations of the radiation pattern from a number of ground-based VLF transmitters by averaging six years of data from the DEMETER satellite. We divide the slice at ∼700 km altitude above a transmitter into pixels and calculate the average field for all satellite passes through each pixel. There are enough data to see 25 km features in the radiation pattern, including the modal interference of the subionospheric signal mapped upwards. Using these data, we deduce the first empirical measure of the radiated power into the magnetosphere from these transmitters, for both daytime and nighttime, and at both the overhead and geomagnetically conjugate region. We find no detectable variation of signal intensity with geomagnetic conditions at low and mid latitudes (L < 2.6). We also present evidence of ionospheric heating by one VLF transmitter which modifies the trans-ionospheric absorption of signals from other transmitters passing through the heated region.read more
Citations
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Past, Present and Future of Active Radio Frequency Experiments in Space
Anatoly V. Streltsov,Anatoly V. Streltsov,Jean-Jacques Berthelier,Alexander Chernyshov,V. L. Frolov,V. L. Frolov,Farideh Honary,Michael Kosch,Michael Kosch,Michael Kosch,R. P. Mccoy,Evgeny Mishin,Michael T. Rietveld +12 more
TL;DR: This review describes the heating facilities, past and present, and discusses scientific results from these facilities and associated space missions, including important satellite missions which are necessary to answer the outstanding questions in this field.
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Inner belt and slot region electron lifetimes and energization rates based on AKEBONO statistics of whistler waves
Oleksiy Agapitov,Oleksiy Agapitov,Oleksiy Agapitov,Anton Artemyev,Anton Artemyev,Didier Mourenas,Yoshiya Kasahara,Vladimir Krasnoselskikh +7 more
TL;DR: In this article, the amplitude distribution of hiss, lightning-generated, and other whistler mode waves from terrestrial VLF transmitters were obtained from the EXOS-D (Akebono) satellite in the Earth's plasmasphere and fitted as functions of L and latitude for two geomagnetic activity ranges (Kp 3).
Journal ArticleDOI
Analysis of experimentally validated trans‐ionospheric attenuation estimates of VLF signals
K. L. Graf,Nikolai Lehtinen,Maria Spasojevic,Morris B. Cohen,Robert A. Marshall,Umran S. Inan,Umran S. Inan +6 more
TL;DR: In this paper, a full wave model for trans-ionospheric propagation is presented, which includes wave polarization, incidence angle, bearing, ground conductivity, horizontal distance from the source, and ionospheric profile.
Journal ArticleDOI
An Investigation of VLF Transmitter Wave Power in the Inner Radiation Belt and Slot Region
Journal ArticleDOI
Models of ionospheric VLF absorption of powerful ground based transmitters
TL;DR: In this article, Cohen et al. used a newly available extensive record of VLF transmitter energy reaching the magnetosphere, taken from the DEMETER satellite, and performed a direct comparison with a sophisticated full wave model of trans-ionospheric propagation.
References
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Journal ArticleDOI
An investigation of whistling atmospherics
TL;DR: In this article, the authors investigated the nature and origin of whistlers, which are sometimes observed at frequencies below 15 kc/s and were found to follow the lines of force of the earth's magnetic field.
Journal ArticleDOI
Electron scattering loss in Earth's inner magnetosphere: 1. Dominant physical processes
Bob Abel,Richard M. Thorne +1 more
TL;DR: Pitch angle diffusion rates due to Coulomb collisions and resonant interactions with plasmaspheric hiss, lightning-induced whistlers and anthropogenic VLF transmissions are computed for inner magnetospheric electrons as discussed by the authors.
Journal ArticleDOI
ICE, the electric field experiment on DEMETER
Jean-Jacques Berthelier,Michel Godefroy,F. Leblanc,M. Malingre,Michel Menvielle,D. Lagoutte,J.-Y. Brochot,Francis Colin,F. Elie,C. Legendre,P. Zamora,D. Benoist,Y. Chapuis,J. Artru,Robert F. Pfaff +14 more
TL;DR: The ICE (Instrument Champ Electrique) experiment on board DEMETER is to provide a nearly continuous survey of the electromagnetic and/or electrostatic waves that may arise from the coupling of seismic activity with the upper atmosphere and ionosphere as discussed by the authors.
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