Plasma-maser Interaction Research Articles

Generation of whistler mode in a relativistic plasma

This paper contains the plasma maser interaction between high frequency nonresonant whistler R-mode and low frequency resonant ion acoustic mode in a relativistic plasma. It shows that the whistler R-mode grows through the plasma maser interaction between the relativistic electrons and the ion acoustic fluctuation.

Study of nonlinear interaction of waves through plasma-maser in magnetosphere plasma

A theoretical study is made on the generation mechanism of electrostatic Bernstein mode wave in the presence of electromagnetic Kinetic Alfven wave turbulence in magnetized inhomogeneous plasma on the basis of plasma-maser interaction. It is shown that a test high-frequency electrostatic Bernstein mode wave is unstable in the presence of low-frequency Kinetic Alfven wave turbulence. Because of the universal existence of the Kinetic Alfven waves in large-scale plasmas, the result has potential importance in space and astrophysical radiation process. The growth rate of the test high-frequency Bernstein mode wave is obtained with the involvement of spatial density gradient parameter. A comparative study on the role of density gradient in the generation of Bernstein mode on the basis of plasma-maser effect is presented.

Study of plasma–maser instability in an inhomogeneous plasma

The plasma–maser, an interesting nonlinear process in plasmas, is an effective means of energy up-conversion in frequency from low-frequency turbulence to a high-frequency wave. A theoretical study is made of the amplification mechanism of an electrostatic Bernstein mode wave in presence of Langmuir wave turbulence in a magnetized inhomogeneous plasma on the basis of a plasma–maser interaction. It is shown that a test high-frequency electrostatic Bernstein mode wave is unstable in the presence of low-frequency Langmuir wave turbulence. The growth rate of a test high-frequency Bernstein mode wave is calculated with the involvement of a spatial density gradient parameter. A comparative study on the role of density gradient in the generation of the Bernstein mode on the basis of the plasma–maser effect is presented.

Plasma-maser instability of the ion acoustics wave in the presence of lower hybrid wave turbulence in inhomogeneous plasma

A theoretical study is made on the generation mechanism of ion acoustics wave in the presence of lower hybrid wave turbulence field in inhomogeneous plasma on the basis of plasma-maser interaction. The lower hybrid wave turbulence field is taken as the low-frequency turbulence field. The growth rate of test high frequency ion acoustics wave is obtained with the involvement of spatial density gradient parameter. A comparative study of the role of density gradient for the generation of ion acoustics wave on the basis of plasma-maser effect is presented. It is found that the density gradient influences the growth rate of ion acoustics wave.

Relativistic plasma maser interaction in the presence of ion acoustic turbulence

The plasma maser interaction between the high frequency nonresonant ordinary mode and low frequency resonant ion acoustic mode in a relativistic plasma has been studied for the first time. It has been shown that the growth rate of the high frequency wave occurs through the plasma maser interaction between relativistic electrons and the ion acoustic wave turbulence.

Theory of Langmuir wave generation in the presence of Alfvén wave turbulence in an electron-positron plasma: Case III

The plasma maser interaction of a test Langmuir wave in the presence of Alfvén wave turbulence is studied theoretically in a magnetized electron-positron (e-p) plasma, where the turbulence is produced by both electron and positron temperature anisotropies. Langmuir waves are generated without the necessity of an electron or positron beam component. The growth takes place in the direction of propagation of the Alfvén waves.

Theory of Langmuir wave generation in the presence of Alfvén wave turbulence in an electron-positron plasma

The plasma maser interaction of the test Langmuir wave in the presence of Alfvén wave turbulence is studied theoretically in a magnetized electron–positron (e-p) plasma where the turbulence is produced by a temperature anisotropy. Langmuir waves are found to grow without the necessity of an electron (or positron) beam component. The growth takes place in a direction opposite to that of Alfvén waves.

Nonlinear plasma maser driven by electron beam instability

The detailed analysis of plasma maser interaction between high-frequency electromagnetic waves with right-handed polarization (R mode) and electrostatic Langmuir waves excited by an electron beam is presented. The analysis shows that generation of R-mode radiation near 2ωpe is possible only for magnetized plasmas; here ωpe is the electron plasma frequency. Simulations using a two-dimensional electromagnetic and relativistic particle code show that high-frequency electromagnetic waves with right-handed polarization (R mode) can be generated by a plasma maser mechanism from electrostatic Langmuir waves excited by an electron beam.

Nonlinear plasma maser driven by electron beam instability

Simulations show that high frequency electromagnetic waves near 2 ω pe with right-handed polarization (R-mode) can be generated by a plasma-maser mechanism from electrostatic Langmuir waves excited by an electron beam. Here ω pe is the electron plasma frequency. The detailed theoretical analysis of plasma-maser interaction can explain most of the characteristics of the simulation results.

Consequences of the plasma-maser instability in magnetized plasma

The total momentum and energy conservation relations for the plasma-maser interaction among the resonant, nonresonant modes, and the electrons are satisfied for magnetized plasma. The Manley-Rowe relation in its original form is violated because the resonant electrons carry nonlinear momentum and energy. The plasma-maser satisfies the generalized Manley-Rowe relation which includes the effective action from resonant electrons in addition to the original one from waves. It is shown that the plasma-maser effect works if there are Onsager symmetry breaking factors such as temperature anisotropy due to external magnetic field, inhomogeneity due to density gradient. The generation mechanism of the electromagnetic radiation is studied based on the plasma-maser interaction among the electrostatic lower hybrid turbulences, accelerated electrons and extraordinary mode radiation. The theory agrees with the most striking and new features of the observation of the auroral kilometric radiation (AKR) in that the AKR bursts are observed at frequencies well above the local electron gyrofrequency.

Conservation relations and the generalized Manley–Rowe relation for the plasma–maser in magnetized plasma

The plasma–maser interaction among Langmuir waves, Bernstein waves, and the electron distribution function on an equal footing is studied. The total momentum and energy conservation relations between electron kinetic energy and wave energy is satisfied for magnetized plasma. The Manley–Rowe relation in its original form is violated because the resonant electrons carry nonlinear momentum and energy. The plasma–maser process satisfies the generalized Manley–Rowe relation which includes the effective action from electrons in addition to the original one from waves.

The evolution of the resonant mode in plasma-maser interaction

We study the evolution of the resonant waves considering its interaction with the nonresonant waves and the plasma particles due to plasma-maser effect. The nonlinear dielectric function of the resonant wave is calculated and is found to consist of two parts: the direct and the polarization coupling terms. On the other hand, the nonlinear dielectric function of the nonresonant wave consists only of the direct coupling term. The significance of our results is discussed.

On the conservation of the nonresonant quanta in plasma–maser interaction

This paper presents an investigation on the conservation of the nonresonant quanta in a new mode-coupling process, namely, the plasma-maser interaction. Considering interaction of ordinary mode electromagnetic wave with Langmuir turbulence in a magnetized plasma, it is shown that the anisotropy induced by the external magnetic field is primarily responsible for the nonconservation of the number of quanta in an open system. In contrast, the number of quanta of the high frequency wave is conserved in a closed system.

Plasma-maser instability of electromagnetic radiation in the presence of lower hybrid turbulence.

The generation mechanism of the electromagnetic radiation is studied based on the plasma-maser interaction among the electrostatic lower hybrid turbulence, accelerated electrons, and extraordinary mode radiation. The theory agrees with the most striking new features of the observation of the auroral kilometric radiation (AKR) in that the AKR bursts are observed at frequencies well above the local electron gyrofrequency. The theory also explains the close correlation between the lower hybrid turbulence and the microwave emission reported based on recent computer simulations.

Plasma–maser instability of the electromagnetic radiation in the presence of the lower hybrid turbulence

The generation mechanism of the electromagnetic radiation is studied based on the plasma–maser interaction among the electrostatic lower hybrid turbulence, accelerated electrons and extraordinary mode radiation. The theory agrees with the most striking new features of the auroral kilometric radiation (AKR) in that the AKR bursts are observed at frequencies well above the local electron gyrofrequency. The theory also explains the close correlation between the lower hybrid turbulence and the microwave emission which is reported by recent computer simulations.

Wave stochasticity and nonlinear plasma–maser effect

Influence of wave stochasticity on the interaction of resonant and nonresonant plasma waves is considered. As the correlations of the resonant waves grow, the plasma-maser interaction becomes more effective. It is demonstrated with an example of resonant Langmuir waves that a rapid decrease of the wave stochasticity due to modulational instability leads to enhanced interaction of nonresonant electromagnetic waves with plasma particles via transition processes.

Plasma-maser interaction of langmuir wave with kinetic Alfvén wave turbulence

A theoretical study is made on the generation mechanism of Langmuir mode wave in the presence of kinetic Alfven wave turbulence in a magnetized plasma on the basis of plasma-maser interaction. It is shown that a test high frequency Langmuir mode wave is unstable in the presence of low frequency kinetic Alfven wave turbulence. The growth of the Langmuir wave occurs due to direct and polarization coupling terms. Because of the universal existence of the kinetic Alfven waves in large scale plasmas, the results have potential importance in space and astrophysical radiation processes.

Electromagnetic emission in a magnetized plasma

We present a theory of emission of electromagnetic waves, in the ordinary and extraordinary modes, in the presence of Langmuir turbulence in a magnetized plasma due to a high frequency nonlinear force. The mechanism of emission considered is the plasma-maser interaction which is essentially an energy up-conversion process. The growth rates of the ordinary and extra-ordinary mode emissions are calculated and the results are compared with those obtained from the direct formulation. The scope of application of the results to radio spectra from solar flares is then stressed.

Physical aspects of the plasma-maser interaction

The plasma-maser interaction of Langmuir waves with ion-acoustic waves and electrons of a plasma and a beam is considered. It is found that the maximum rates of the plasma-maser instability are connected with the stochastic properties of the nonresonant ion-sound turbulence and those of the resonant Langmuir waves. The condition for dominance of te plasma-maser effect over the linear Landau instability is obtained. The physical aspects of the plasma-maser interaction are discussed.

Plasma maser interaction with magnetohydrodynamic wave turbulence

The energy up-conversion from the kinetic Alfvén wave turbulence to the ordinary mode radiation through the plasma-maser process is studied. The growth rate of the ordinary mode originates from two mode-mode coupling terms, viz: the direct and polarization terms. In contrast to the previous electrostatic wave case, both contributions give large growth rate for the ordinary mode radiation. The results have potential importance to interpret numerous astrophysical radio phenomena, because the magneto-hydrodynamic (MHD) waves contain the dominant turbulent fluctuations in astrophysical plasmas.