The evolution of electrostatic waves and excitation of instabilities in two-component streaming plasmas in a magnetic field are analytically studied. The modified spectrum and growth term of instability are derived to explain the physical situations like cold plasma, warm plasma, ion fusion aspect along with the uncoupled mode. The striking features of the analysis are displayed in the form of profiles of the refractive index (η) varying with particle thermal energy (KT) in different streaming regimes (V0). The effect of streaming enhances the frequency propagation of waves or dispersion, including phase velocity and refractive indices. However, the damping or growth term of instability is diminished, appreciably owing to the streaming. The findings may have important implications to space and magnetospheric settings where a beam–plasma interaction exists.

Nonlinear interaction between electrostatic waves propagating obliquely to an ambient uniform magnetic field, and electron plasma in relativistic formalism are analyzed in detail. Resonances among the harmonics (l) are delineated and a qualitative expression for the overlapping parameter (K) leading to stochasticisty is analytically derived. A novel feature of this analysis is revealed in the form of threshold wave amplitude (φk), especially at the onset of chaos. The interesting profiles concerning the variation of threshold amplitude with harmonics (l), magnetic field lines (B0), and wave vector (kz) pertaining to ensemble of electrostatic waves are displayed and discussed along with the phase-space topology mappings. These findings may provide important information concerning astrophysical scenarios, which include intergalactic plasmas, cosmic plasma particles, synchrotron radiation, and pulsar plasma analysis.

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Thomson scattering measurement of the beatwave excited relativistic plasma waves AIP Conf.Induced transparency and parametric instabilities in the relativistic regime of the laser plasma interaction AIP Conf.Explicit results pertaining to nonlinear oscillation and triggering of chaos in a relativistic magnetoactive beam-plasma system, which shows transient or streaming phenomena, are analytically presented. The phase-space mappings and their striking features, both in strong streaming and nonstreaming situations, are shown. A new feature concerning streaming plasma analysis is revealed in the form of frequency modulation, especially at the onset of chaos, including varying k z pertaining to an ensemble of electrostatic waves. It is further shown that the modulation frequency is governed by marked cutoff values, corresponding to varying magnetic field lines, and that it approaches a steady value with the rise in the streaming parameter. Our findings may have important implications for astrophysical settings where there beam-plasma interactions exist.

An ensemble of electrostatic waves propagating obliquely to the external uniform magnetic field accelerates the plasma electrons, giving rise to a mechanical energy in terms of finite magnetic moment ͑͒. In nonlinear analysis, this magnetic moment modifies the resonances among the harmonics (l) and the overlapping parameter (K) leading to stochasticity. It is shown that the threshold amplitude ( k ) of electrostatic waves at the onset of chaos increases slowly for lϭ0 harmonics and sharply for higher harmonics (lу1), owing to the effect of magnetic moment. A sharp decrease of threshold amplitude with wave vector ͑k͒ pertaining to the ensemble of waves for higher harmonics (lу1) is also delineated. The findings may have astrophysical and cosmological signatures in the high energy particle regimes.