Autor: |
Pramanik, Sourav, Maity, Chandan, Karmakar, Mithun |
Předmět: |
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Zdroj: |
Physics of Plasmas; Aug2019, Vol. 26 Issue 8, pN.PAG-N.PAG, 7p, 3 Graphs |
Abstrakt: |
In a fluid approach, nonlinear evolution of electrostatic lower hybrid modes is studied in a cold magnetized electron-ion plasma. The background magnetic field is assumed to be constant. In the frequency range of interest Ωci ≪ ω ≪ Ωce, the massive ions are treated as unmagnetized, and the electron inertia in the x-component of the momentum equation is neglected. The quasineutral plasma approximation is also relaxed. The dispersion relation for such low frequency modes reads as ω 2 = ω pi 2 / (1 + ω pe 2 / Ω ce 2). Spatiotemporal evolution of such modes is analyzed by employing a simple perturbation technique. Our results show that an initially excited lower hybrid mode gradually loses its coherent nature due to phase mixing and eventually breaks even at an arbitrarily low amplitude. An estimate of the phase mixing time is also given, and it is found to increase as the strength of the magnetic field is enhanced. These results will be of relevance to space plasma situations and laboratory experiments. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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