Methods in Nonlinear Plasma Theory

Nonlinear dynamics of the magnetic electron drift mode turbulence is outlined and generation of large-scale magnetic structures in a nonuniform unmagnetized plasma by turbulent Reynolds stress is demonstrated. A two-component turbulent system consisting of magnetic fluctuations and generated secondary flows is considered. The evolution equations for mean magnetic flow generation are obtained by averaging the two-field model equations over fast small scales. It is found, in turn, that the pattern of the flow modulates and regulates the turbulence dynamics. The main features of the flows are controlled by the structure of the nonlinear coupling to the small-scale magnetic fluctuations as well as by the spectral properties of the turbulence and its anisotropy. Thus, the parent waves and secondary magnetic flows form a self-regulating system. It is shown that the presence of large-scale structures leads to shearing of turbulence. The k-space diffusion coefficient for the magnetic zonal flows and streamers are calculated.

Section: B Dynamics Of Magnetic Electron Drift Modes In the Presencementioning

confidence: 99%

Generation of large-scale magnetic flows in turbulent plasma

Andrushchenko

Павленко

2004

“…The whistler wave fields are E l ϭ(E lx ,E ly ,0) and B l ϭ(B lx ,B ly ,0). The interaction of the turbulent fields with electrons that leads to the R-mode radiation test wave is governed by the Vlasov-Maxwell equations, 10,11 …”

Section: Dispersion Function Of the R-modementioning

confidence: 99%

Numerical simulation and theory of generation of electromagnetic waves in the presence of whistler turbulence

Bujarbarua

Nambu²,

Saikia

et al. 1998

The generation of R-mode electromagnetic waves from whistler turbulence by plasma maser effect is studied both numerically and theoretically. Simulations using a two-dimensional electromagnetic and relativistic particle code show that high frequency electromagnetic waves with right-handed polarization ͑R-mode͒ can be generated by a plasma maser mechanism from low frequency whistler waves excited by electron temperature anisotropy. Results obtained theoretically are in good agreement with numerical findings.

“…According to the standard method, 13 after lengthy but straightforward calculations, we obtain the nonlinear dielectric constant of the Langmuir wave ͓⑀ h (K,⍀)͔ in the presence of the whistler mode turbulence as follows ͑see the Appendix͒:…”

Section: Nonlinear Dielectric Constant Of the Langmuir Wave In Thmentioning

confidence: 99%

Plasma maser with cyclotron resonance

Nambu

Sakai

1997

The plasma-maser process, including whistler mode turbulence and a test Langmuir wave, is considered for weakly magnetized plasma pe Ͼ⍀ e , where pe and ⍀ e are the electron plasma and cyclotron frequency, respectively. The cyclotron resonant interaction between electrons and whistler mode is effective for the growth of the Langmuir wave through the plasma-maser process. The unstable test Langmuir wave and the whistler mode propagate in opposite directions. The direct coupling contribution exactly cancels out with the reverse absorpting effect due to the quasi-linear effect. The polarization coupling contribution gives the plasma-maser effect. The theory can explain a recent numerical simulation.