Possible wave modes of wideband nonthermal continuum radiation in its source region

0357107 - ÚFA 2011 RIV US eng J - Článek v odborném periodiku
Grimald, S. - Santolík, Ondřej
Possible wave modes of wideband nonthermal continuum radiation in its source region.
Journal of Geophysical Research. Roč. 115, - (2010), A06209/1-A06209/8. ISSN 0148-0227
Grant CEP: GA ČR GA205/09/1253; GA MŠMT ME09107
Grant ostatní: ESA(XE) PECS98025
Výzkumný záměr: CEZ:AV0Z30420517
Klíčová slova: nonthermal continuum * NTC * wave modes
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
Impakt faktor: 3.303, rok: 2010

Nonthermal continuum (NTC) electromagnetic radiation is generated within the Earth’s magnetosphere and radiated to the outer space. We present cases of a specific type of NTC, which appears as multiple wide bands on the spectrograms recorded by the Cluster spacecraft just outside the plasmapause. This NTC comes from several sources located in the plasmapause density gradient where the local upper hybrid frequency is close to the harmonics of the electron cyclotron frequency. Analysis of one of these events at the eighth harmonic frequency indicates that, in the vicinity of the source, the electric field fluctuations are polarized in the plane perpendicular to the magnetic field line. Hot-plasma dispersion relation based on the measured electron distribution shows that the observed polarization excludes the presence the Langmuir mode and the ordinary mode.
Trvalý link: http://hdl.handle.net/11104/0195454