ISSN:
1089-7674
Quelle:
AIP Digital Archive
Thema:
Physik
Notizen:
The propagation of an intense electromagnetic wave (EMW), of frequency 9 GHz, in an underdense, near critical, inhomogeneous plasma (ne≤1.2×1012 cm−3, Te(similar, equals)3 eV) leads to an up-shift of the EMW frequency of a few MHz. The injected EMW with power, P0≤250 kW, and with pulse duration of 1 μs, produces additional ionization of the neutral argon gas (n0(similar, equals)6.6×1013 cm−3) through the heating of plasma electrons. The increase of plasma density, which can reach during the EMW pulse several tens of percents in relative value, leads to a modulation in time of the spatial phase of the EMW. Experimental results for the evolution in space and in time of density, electric field, and frequency shift are compared to a simple nonlinear model of EMW propagation in a plasma, which takes into account the additional ionization due to the absorption of the EMW. © 1997 American Institute of Physics.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.872416
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