scholarly journals Kinetic theory of electrostatic ion cyclotron waves (QPESIC) in multicomponent plasmas with negative ions

2007 ◽  
Vol 5 (1) ◽  
pp. 45-55 ◽  
Author(s):  
Darko Simic ◽  
Dragan Gajic
Keyword(s):  
Kinetic Theory ◽  
Negative Ions ◽  
Negative Ion ◽  
Bgk Model ◽  
Maxwellian Plasma ◽  
Ion Cyclotron ◽  
Model Collision ◽  
Weakly Ionized ◽  
Component Plasma ◽  
Ion Species

The instabilities of the quasi-perpendicular electrostatic (?B = 0) ioncyclotron waves (QPESIC) are investigated. The kinetic theory with BGK model collision integrals is used to estimate the critical electron drift velocity in the presence of positively or negatively charged resonant ions in multi-component plasma. Analytical evaluation for the ion-cyclotron modes and instabilities in the long-wave range in a weakly-ionized Maxwellian plasma with two positive ion species, one negative ion species and with electrons, drifting along magnetic lines of force is demonstrated. The spectrum in these situations is also given. It is shown that the critical drift decreases as the state of plasma approaches the isothermic state.

Excitation of long-wave quasi-perpendicular electrostatic ion-cyclotron waves in multi-species weakly ionized plasmas

1990 ◽  
Vol 43 (1) ◽  
pp. 23-50 ◽  
Author(s):  
B. S. Milić
Keyword(s):  
Kinetic Equations ◽  
Mean Free Path ◽  
Bgk Model ◽  
Instability Waves ◽  
Background Magnetic Field ◽  
Ion Cyclotron ◽  
Model Collision ◽  
Weakly Ionized ◽  
Electron Mean Free Path ◽  
Ion Species

It is shown, using kinetic equations with BGK model collision integrals, that in a multi-species weakly ionized plasma the quasi-perpendicular ion-cyclotron instability (waves of growing amplitude) excited by the electron drift parallel to the background magnetic field first sets in for long waves (modal wavelengths much larger than the electron mean free path) as the drift is gradually increased, much as in plasmas with only one ion species. Only waves with modal frequencies close to some cyclotron harmonics of some of the ion species present are taken into account in the present work. Owing to the mutual commensurability of all the ion-cyclotron frequencies, more than one species of ions may be ‘resonant’ with any mode of the type considered. The role of ‘resonant’ and ‘non-resonant’ ion species is investigated, both in general and for some particular plasmas. Some numerical details are also given. It is shown that although in most instances the threshold drifts vary monotonically (but not linearly) as the plasma composition is varied, there are cases in which maxima or minima (often depending on the degree of non-isothermality) of the threshold drift magnitude are predicted for some specific plasma compositions. These are usually encountered in plasmas containing ions with different charge numbers.

Instability of higher harmonic electrostatic ion cyclotron waves in a negative ion plasma

2009 ◽  
Vol 75 (4) ◽  
pp. 495-508 ◽  
Author(s):  
M. ROSENBERG ◽  
R. L. MERLINO
Keyword(s):  
Negative Ions ◽  
Negative Ion ◽  
Theory Analysis ◽  
Positive Ions ◽  
Ion Cyclotron Waves ◽  
Laboratory Plasmas ◽  
Ion Cyclotron ◽  
Higher Harmonic ◽  
Parameter Ranges ◽  
Ion Species

AbstractWe present a kinetic theory analysis of the electrostatic ion cyclotron (EIC) instability in a plasma containing positive ions, electrons, and negative ions that are much more massive than the positive ions. Conditions are investigated for exciting the fundamental and the higher harmonic EIC waves associated with each ion species. We find that as the concentration of heavy negative ions increases, the wave frequencies increase, the unstable spectrum in general shifts to longer perpendicular wavelengths, and the growth of higher harmonic EIC waves tends to increase within certain parameter ranges. Applications to possible laboratory plasmas are discussed.

Linear and nonlinear obliquely propagating ion-acoustic waves in magnetized negative ion plasma with non-thermal electrons

2013 ◽  
Vol 79 (5) ◽  
pp. 893-908 ◽  
Author(s):  
M. K. MISHRA ◽  
S. K. JAIN
Keyword(s):  
Acoustic Waves ◽  
Kdv Equation ◽  
Negative Ions ◽  
Ion Concentration ◽  
Negative Ion ◽  
Slow Mode ◽  
Ion Temperature ◽  
Ion Acoustic ◽  
Ion Acoustic Solitons ◽  
Ion Species

AbstractIon-acoustic solitons in magnetized low-β plasma consisting of warm adiabatic positive and negative ions and non-thermal electrons have been studied. The reductive perturbation method is used to derive the Korteweg–de Vries (KdV) equation for the system, which admits an obliquely propagating soliton solution. It is found that due to the presence of finite ion temperature there exist two modes of propagation, namely fast and slow ion-acoustic modes. In the case of slow-mode if the ratio of temperature to mass of positive ion species is lower (higher) than the negative ion species, then there exist compressive (rarefactive) ion-acoustic solitons. It is also found that in the case of slow mode, on increasing the non-thermal parameter (γ) the amplitude of the compressive (rarefactive) soliton decreases (increases). In fast ion-acoustic mode the nature and characteristics of solitons depend on negative ion concentration. Numerical investigation in case of fast mode reveals that on increasing γ, the amplitude of compressive (rarefactive) soliton increases (decreases). The width of solitons increases with an increase in non-thermal parameters in both the modes for compressive as well as rarefactive solitons. There exists a value of critical negative ion concentration (αc), at which both compressive and rarefactive ion-acoustic solitons appear as described by modified KdV soliton. The value of αc decreases with increase in γ.

Wavenumber shift of an obliquely propagating ion-cyclotron whistler

1989 ◽  
Vol 41 (1) ◽  
pp. 37-44 ◽  
Author(s):  
S. N. Paul ◽  
A. K. Sur ◽  
G. Pakira
Keyword(s):  
Cyclotron Frequency ◽  
Negative Ions ◽  
Ion Concentration ◽  
Negative Ion ◽  
Propagation Angle ◽  
Ion Cyclotron ◽  
Numerical Estimations

An expression for the nonlinear wavenumber shift of an obiquely propagating ion-cyclotron whistler in the presence of negative ions are derived. The effects of the intensity of the wave, the ion-cyclotron frequency, the negative-ion concentration and the propagation angle on the wavenumber shift of whistlers is discussed. Numerical estimations are also made of the wavenumber shift.

Excitation of electromagnetic quasi-perpendicular ion cyclotron waves in collisional plasmas

1983 ◽  
Vol 29 (1) ◽  
pp. 21-34 ◽  
Author(s):  
B. S. Milić ◽  
N. R. Brajušković
Keyword(s):  
Electromagnetic Waves ◽  
Kinetic Equations ◽  
Mean Free Path ◽  
Electron Drift ◽  
Bgk Model ◽  
Plasma Parameters ◽  
Electron Collisions ◽  
Ion Cyclotron Waves ◽  
Ion Cyclotron ◽  
Weakly Ionized

The process of spontaneous excitation of electromagnetic (non-potential) and quasi-perpendicular (with respect to the external magnetic field) ion cyclotron waves by electron drift in a weakly ionized plasma is analysed. An infinite plasma placed in mutually parallel d.c. electric and magnetic fields is considered, and its dynamics is described by kinetic equations with BGK model collision integrals. The threshold electron drift necessary for the onset of the corresponding ion cyclotron instability is evaluated. It is shown that the instability sets in first for wavelengths much larger than the electron mean free path, so that the electron collisions, dominant in this range of wavelengths, play a facilitating rather than an impeding role in this process. The results are compared with those for the spontaneous excitation of electrostatic (potential) quasi-perpendicular ion cyclotron waves and, for the same set of plasma parameters, the threshold drift is found to be smaller for the electromagnetic waves.

Propagation of nonlinear electrostatic drift solitary waves in a collisionless plasma consisting of two ion species

1977 ◽  
Vol 55 (10) ◽  
pp. 861-865
Author(s):  
S. G. Tagare
Keyword(s):  
Solitary Wave ◽  
Solitary Waves ◽  
Collisionless Plasma ◽  
Argon Plasma ◽  
Negative Ions ◽  
Ionic Species ◽  
Ion Concentration ◽  
Negative Ion ◽  
Light Ions ◽  
Ion Species

A modified two-dimensional Korteweg – de Vries equation for a collisionless plasma consisting of two distinct ionic species and isothermal electrons has been derived. The effect of concentration of light ions on the amplitude and the width of the drift solitary wave is examined for an argon plasma and a helium plasma with hydrogen ion impurities. Similarly the effect of concentration of negative ions on the amplitude of the drift solitary wave is examined and it is shown that when negative ions are present one gets the usual compressive drift solitary waves with positive amplitude as well as rarefactive drift solitary waves with negative amplitude depending on the negative ion concentration.

Drift instability in a positive ion–negative ion plasma

2013 ◽  
Vol 79 (5) ◽  
pp. 949-952 ◽  
Author(s):  
M. ROSENBERG ◽  
R. L. MERLINO
Keyword(s):  
Negative Ions ◽  
Local Approximation ◽  
Magnetized Plasma ◽  
Negative Ion ◽  
Positive Ions ◽  
Ion Plasma ◽  
Drift Instability ◽  
Ion Species ◽  
Positive Ion ◽  
Linear Kinetic Theory

AbstractDrift wave instability in a magnetized plasma composed of positive ions and negative ions is considered using linear kinetic theory in the local approximation. We consider the case where the mass (temperature) of the negative ions is much larger (smaller) than that of the positive ions, and where the gyroradii of the two ion species are comparable. Weak collisional effects are taken into account. Application to possible laboratory parameters is discussed.

scholarly journals Nonlinear Shift of Wave Parameters of Whistlers in the Ionosphere in the Presence of Negative Ions

1987 ◽  
Vol 40 (5) ◽  
pp. 665 ◽  
Author(s):  
AK Sur ◽  
PK Kashyapi ◽  
SN Paul ◽  
B Chakraborty
Keyword(s):  
Cyclotron Frequency ◽  
Negative Ions ◽  
Wave Frequency ◽  
Ion Concentration ◽  
Negative Ion ◽  
Wave Number ◽  
Wave Parameters ◽  
Ion Cyclotron

In this paper the nonlinear shift of the wave number of ion-cyclotron whistlers propagating through the ionosphere in the presence of negative ions is estimated. The results are discussed both numerically and graphically for the proton whistler. It is seen that under some physical situations the nonlinear shift of the wave number of the proton whistler is very significant. Furthermore, the nonlinear shift of the wave number depends significantly on the variation of negative ion concentration when the wave frequency is very close to an ion-cyclotron frequency.

scholarly journals Study of ion-acoustic solitary wave structures in multi-component plasma containing positive and negative ions and q-exponential distributed electron beam

2017 ◽  
Vol 35 (4) ◽  
pp. 641-647 ◽  
Author(s):  
J. Sarkar ◽  
J. Goswami ◽  
S. Chandra ◽  
B. Ghosh
Keyword(s):  
Electron Beam ◽  
Solitary Wave ◽  
Small Amplitude ◽  
Dense Plasma ◽  
Perturbation Technique ◽  
Negative Ions ◽  
Negative Ion ◽  
Ion Acoustic ◽  
Component Plasma ◽  
Streaming Motion

AbstractUsing reductive perturbation technique, small-amplitude ion-acoustic solitary wave has been investigated in multi-component dense plasma, in which an electron beam propagates along the general streaming motion. The electrons in plasma have the q-exponential distribution. The positive and negative ions follow a regular Maxwellian distribution. It has been found that the positive and negative ion densities as well as the beam concentration have significant effect on the formation and properties of solitary structures. The streaming velocities of corresponding particles also have pronounced effect on the features of the solitons.

Obliquely propagating ion-acoustic solitons in a multi-component magnetized plasma with negative ions

1994 ◽  
Vol 52 (3) ◽  
pp. 409-429 ◽  
Author(s):  
M. K. Mishra ◽  
R. S. Chhabra ◽  
S. R. Sharma
Keyword(s):  
Soliton Solution ◽  
Kdv Equation ◽  
Critical Concentration ◽  
Negative Ions ◽  
Magnetized Plasma ◽  
Negative Ion ◽  
Fast Mode ◽  
Ion Acoustic ◽  
Ion Acoustic Solitons ◽  
Ion Species

Oblique propagation of ion-acoustic solitons in a magnetized low-β plasma consisting of warm positive and negative ion species along with hot electrons is studied. Using the reductive perturbation method, a KdV equation is derived for the system, which admits an obliquely propagating soliton solution. It is found that if the ions have finite temperatures then there exist two types of modes, namely slow and fast ion-acoustic modes. The parameter determining the nature of soliton (i.e. whether the system will support compressive or rarefactive solitons) is different for slow and fast modes. For the slow mode the parameter is the relative temperature of the two ion species, whereas for the fast mode it is the relative concentraion of the two ion species. For the fast mode it is found that there is a critical value of the negative-ion concentration below which only compressive solitons exist and above which rarefactive solitons exist. To discuss the soliton solution at the critical concentration, a modified KdV equation is derived. It is found that at the critical concentration of negative ions compressive and rarefactive solitons co-exist. The effects of temperature of different ion species, angle of obliqueness and magnetization on the characteristics of the solitons are discussed in detail.

Sign in / Sign up

Export Citation Format

Share Document