Magnetoacoustic Nonlinear Solitary and Freak Waves in Pair-Ion Plasma

2019 ◽  
Vol 74 (9) ◽  
pp. 777-786 ◽  
Author(s):  
Papihra Sethi ◽  
Kuldeep Singh ◽  
N.S. Saini
Keyword(s):  
Solitary Wave Solution ◽  
Reductive Perturbation Method ◽  
Number Density ◽  
Kp Equation ◽  
Temperature Ratio ◽  
Plasma Parameters ◽  
Freak Waves ◽  
Positive Ions ◽  
Ion Plasma ◽  
Magnetohydrodynamic Model

AbstractAn investigation of magnetoacoustic nonlinear solitary and freak waves in a magnetised collisionless pair-ion plasma using two-dimensional magnetohydrodynamic model is presented. The reductive perturbation method is used to obtain the Kadomtsev–Petviashvili (KP) equation. The solitary wave solution of KP equation is examined. Further, on modulating KP equation, the nonlinear Schrödinger equation is derived with the help of appropriate transformation. The influence of various plasma parameters such as magnetic field strength, number density of ions, and temperature ratio of negative to positive ions, etc. on the propagation characteristics of solitary waves and first- as well as second-order magnetoacoustic freak waves in pair-ion plasma is examined.

Solitary and freak waves in superthermal plasma with ion jet

2012 ◽  
Vol 79 (3) ◽  
pp. 287-294 ◽  
Author(s):  
U. M. ABDELSALAM
Keyword(s):  
Solitary Wave Solution ◽  
Kdv Equation ◽  
Ion Beam ◽  
Negative Ions ◽  
Reductive Perturbation Method ◽  
Dust Particles ◽  
Superthermal Electrons ◽  
Plasma Parameters ◽  
Freak Waves ◽  
Superthermal Plasma

AbstractThe nonlinear solitary and freak waves in a plasma composed of positive and negative ions, superthermal electrons, ion beam, and stationary dust particles have been investigated. The reductive perturbation method is used to obtain the Korteweg-de Vries (KdV) equation describing the system. The latter admits solitary wave solution, while the dynamics of the modulationally unstable wavepackets described by the KdV equation gives rise to the formation of freak/rogue excitation described by the nonlinear Schrödinger equation. In order to show that the characteristics of solitary and freak waves are influenced by plasma parameters, relevant numerical analysis of appropriate nonlinear solutions are presented. The results from this work predict nonlinear excitations that may associate with ion jet and superthermal electrons in Herbig–Haro objects.

Nonlinear magnetoacoustic waves in pair-ion plasma with dust impurity

2013 ◽  
Vol 79 (5) ◽  
pp. 825-831 ◽  
Author(s):  
SHI-SEN RUAN ◽  
JIANG-HONG MAN ◽  
SHAN WU ◽  
ZE CHENG
Keyword(s):  
Magnetic Field Intensity ◽  
Vries Equation ◽  
Reductive Perturbation Method ◽  
Dust Particles ◽  
Number Density ◽  
Nonlinear Properties ◽  
Variation Of Parameters ◽  
Ion Plasma ◽  
Magnetoacoustic Waves ◽  
Reductive Perturbation

AbstractNonlinear properties of magnetoacoustic waves are investigated in magnetized pair-ion plasmas with dust impurity. Three-fluid collisionless magneto-hydrodynamic model is considered and reductive perturbation method is employed to derive Korteweg-de Vries equation for magnetoacoustic solitary waves (MASWs). The effects of the charge number of dust particles, magnetic field intensity, and plasma number density are studied on MASWs. It is found that the variation of parameters causes significant changes in solitary structures. The present investigation may be useful to understand formation and propagation of MASW structures in dust pair-ion plasmas.

Third-order contributions to ion-acoustic solitons in a plasma with two types of cold positive ions and two-temperature non-isothermal electrons

2000 ◽  
Vol 64 (3) ◽  
pp. 297-308 ◽  
Author(s):  
S. R. MAJUMDAR ◽  
S. N. PAUL ◽  
K. P. DAS
Keyword(s):  
Solitary Wave ◽  
Solitary Wave Solution ◽  
Reductive Perturbation Method ◽  
Third Order ◽  
Positive Ions ◽  
Ion Acoustic ◽  
Ion Acoustic Solitons ◽  
Ion Acoustic Soliton ◽  
Pseudo Potential ◽  
Two Temperature

Higher-order nonlinear and dispersive effects on ion-acoustic solitons in a plasma consisting of two types of cold positive ions and two-temperature non-isothermal electrons are studied using a reductive perturbation method. An integrated form of the basic sets of fluid equations consisting of two types of positive ions and two types of non-isothermal electrons is derived in terms of a pseudo-potential. A perturbation solution of this equation is obtained by the Bogoliubov–Mitropolsky method. At the lowest order, we obtain a modified Korteweg–de Vries solitary-wave solution, which has a sech4 profile. Calculations are carried out at the next two higher orders. The secularity-removing condition at each order gives a correction to the velocity of the solitary wave at the corresponding order. The variations of Mach number and width of the ion-acoustic soliton with amplitude at each order are shown graphically for plasmas with H+ and He+ or with He+ and Ar+ ions, with two-temperature non-isothermal electrons.

Compressive and rarefactive dust ion-acoustic solitary waves with degenerate electron–positron–ion plasma

2015 ◽  
Vol 81 (3) ◽  
Author(s):  
K. N. Mukta ◽  
M. S. Zobaer ◽  
N. Roy ◽  
A. A. Mamun
Keyword(s):  
Solitary Waves ◽  
Solitary Wave Solution ◽  
Reductive Perturbation Method ◽  
Nonlinear Propagation ◽  
Degenerate Electron ◽  
Plasma Parameters ◽  
Solitary Structures ◽  
Ion Acoustic ◽  
Basic Features ◽  
Dia Waves

The nonlinear propagation of dust ion-acoustic (DIA) waves in a unmagnetized collisionless degenerate dense plasma (containing degenerate electron and positron, and classical ion fluids) has been theoretically investigated. The K-dV equation has been derived by employing the reductive perturbation method and by taking into account the effect of different plasma parameters in plasma fluid. The stationary solitary wave solution of K-dV equation is obtained, and numerically analyzed to identify the basic properties of DIA solitary structures. It has been shown that depending on plasma parametric values, the degenerate plasma under consideration supports compressive or rarefactive solitary structures. It has been also found that the effect of pressures on electrons, ions, and positrons significantly modify the basic features of solitary waves that are found to exist in such a plasma system. The relevance of our results in astrophysical objects such as white dwarfs and neutron stars, which are of scientific interest, is discussed briefly.

The spacecraft wake as a tool to detect cold ions: Turning a problem into a feature

2021 ◽  
Author(s):  
Mats André ◽  
Anders I. Eriksson ◽  
Yuri V. Khotyaintsev ◽  
Sergio Toledo-Redondo
Keyword(s):  
Electric Field ◽  
Plasma Parameters ◽  
Double Probe ◽  
Positive Ions ◽  
Collisionless Plasmas ◽  
Mass Outflow ◽  
Wake Effects ◽  
In Situ Observations ◽  
Positively Charged

<p>Wakes behind scientific spacecraft caused by supersonic drifting ions is common in collisionless plasmas. Such wakes change the local plasma conditions and disturb in situ observations of the geophysical plasma parameters. We concentrate on observations of the electric field with double-probe instruments. Sometimes the wake effects are caused by the spacecraft body, are minor and easy to detect, and can be compensated for in a reasonable way. We show an example from the Cluster spacecraft in the solar wind. Sometimes the effects are caused by an electrostatic structure around a positively charged spacecraft causing an enhanced wake and major effects on the local plasma. Here observations of the geophysical electric field with the double-probe technique becomes impossible. Rather, the wake can be used to detect the presence of cold positive ions. Together with other instruments, also the cold ion flux can be estimated. We discuss such examples from the Cluster spacecraft in the magnetospheric lobes. For an intermediate range of parameters, when the drift energy of the ions is comparable to the equivalent charge of the spacecraft, also the charged wire booms of a double-probe instrument must be taken into account to extract useful information from the observations. We show an example from the MMS spacecraft near the magnetopause. With understanding of the physics causing wakes behind spacecraft, the local effects can sometimes be compensated for. When this is not possible, sometimes entirely new geophysical parameters can be estimated. An example is the flux of cold positive ions, constituting a major part of the mass outflow from planet Earth, using electric and magnetic field instruments on a spacecraft charged due to photoionization</p><p> </p>

Ion-acoustic solitons in multi-component plasmas including negative ions at critical densities

1988 ◽  
Vol 39 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Frank Verheest
Keyword(s):  
Negative Ions ◽  
Stationary Solutions ◽  
Reductive Perturbation Method ◽  
Positive Ions ◽  
Kdv Equations ◽  
Basic Fluid ◽  
Ion Acoustic ◽  
Ion Acoustic Solitons ◽  
Modified Kdv Equations ◽  
Fast Ion

Ion-acoustic solitons in a plasma with different adiabatic ion constituents and isothermal electrons are studied via a reductive perturbation method. The basic fluid equations then give rise to KdV or modified KdV equations, depending upon the relative ion densities. At critical densities, rarefactive and compressive fast ion-acoustic solitons are possible. Explicit stationary solutions are discussed in the special case of cold ions, in a plasma containing two species of negative ions and one of positive ions. The inclusion of heavier ions, even at low densities, increases the amplitudes of the critical solitons.

scholarly journals Excitation and analytical characteristics of an ethanol loaded U-shaped arc

2003 ◽  
Vol 68 (2) ◽  
pp. 109-118 ◽  
Author(s):  
Marija Raskovic ◽  
Ivanka Holclajtner-Antunovic ◽  
Mirjana Tripkovic ◽  
Dragan Markovic
Keyword(s):  
Spectral Line ◽  
Electron Number Density ◽  
Ethanol Solution ◽  
Number Density ◽  
Electron Number ◽  
Plasma Parameters ◽  
Line Intensities ◽  
Ethanol Addition ◽  
Plasma Characteristics ◽  
Dc Arc

The effect of the ethanol load on the discharge and analytical parameters of an argon stabilized U-shaped DC arc has been recorded. Measurements of the radial distribution of the apparent temperatures and the electron number density of the DC plasma showed that ethanol addition causes a decrease in both plasma parameters. The changes in the plasma characteristics, as well as in transport and atomisation processes of the analyte cause a general change in the spectral line intensities, which depends on the physical characteristics of the analyte and the quantity of ethanol loaded into the plasma. Improved detection limits were obtained for V and Mn when a 10%(v/v) water?ethanol solution was nebulized into the plasma.

Magnetic and temperature effects on the energy loss rate of test ions

1983 ◽  
Vol 29 (1) ◽  
pp. 131-137 ◽  
Author(s):  
M. H. A. Hassan ◽  
P. H. Sakanaka
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Energy Loss ◽  
Temperature Effects ◽  
Loss Rate ◽  
Temperature Ratio ◽  
Injection Angle ◽  
Energy Loss Rate ◽  
Ion Plasma ◽  
The Magnetic Field

The energy loss rate, Ė, of test ions injected with velocity V into a Maxwellian electron-ion plasma in the presence of an external magnetic field, is studied. Most of the integrals appearing in the expression for Ė are evaluated analytically and the remaining integrals are evaluated numerically for various values of the parameters η = Ωe / ωe, x = V/ve, r = Te/Ti, and the angle of injection θ. It is shown that the effect of the magnetic field is rather small except for η > 1, the temperature ratio is important for small x (x ≤ 0·2), and the injection angle is not important.

scholarly journals Magnetic field effect on laser-induced breakdown spectroscopy and surface modifications of germanium at various fluences

2017 ◽  
Vol 35 (1) ◽  
pp. 159-169 ◽  
Author(s):  
H. Iftikhar ◽  
S. Bashir ◽  
A. Dawood ◽  
M. Akram ◽  
A. Hayat ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electron Temperature ◽  
Surface Modifications ◽  
Laser Induced Breakdown Spectroscopy ◽  
Excitation Temperature ◽  
Number Density ◽  
Plasma Parameters ◽  
Breakdown Spectroscopy ◽  
Laser Induced Breakdown ◽  
The Magnetic Field

AbstractThe effect of the transverse magnetic field on laser-induced breakdown spectroscopy and surface modifications of germanium (Ge) has been investigated at various fluences. Ge targets were exposed to Nd: YAG laser pulses (1064 nm, 10 ns, 1 Hz) at different fluences ranging from 3 to 25.6 J/cm2 to generate Ge plasma under argon environment at a pressure of 50 Torr. The magnetic field of strength 0.45 Tesla perpendicular to the direction of plasma expansion was employed by using two permanent magnets. The emission spectra of laser-induced Ge plasma was detected by the laser-induced breakdown spectroscopy system. The electron temperature and number density of Ge plasma are evaluated by using the Boltzmann plot and stark broadening methods, respectively. The variations in emission intensity, electron temperature (Te), and number density (ne) of Germanium plasma are explored at various fluences, with and without employment of the magnetic field. It is observed that the magnetic field is responsible for significant enhancement of both excitation temperature and number density at all fluences. It is revealed that an excitation temperature increases from Te,max,without B = 16,190 to Te,max,with B = 20,123 K. Similarly, the two times enhancement in the electron density is observed from ne,max,without B = 2 × 1018 to ne,max,with B = 4 × 1018 cm−3. The overall enhancement in Ge plasma parameters in the presence of the magnetic field is attributed to the Joule heating effect and adiabatic compression. With increasing fluence both plasma parameters increase and achieve their maxima at a fluence of 12.8 J/cm2 and then decrease. In order to correlate the plasma parameters with surface modification, scanning electron microscope analysis of irradiated Ge was performed. Droplets and cones are formed for both cases. However, the growth of ridges and distinctness of features is more pronounced in case of the absence of the magnetic field; whereas surface structures become more diffusive in the presence of the magnetic field.

scholarly journals Ion acoustic quasi-soliton in an electron-positron-ion plasma with superthermal electrons and positrons

Open Physics ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 563-567 ◽  
Author(s):  
Jianyong Wang ◽  
Ying Zeng ◽  
Zufeng Liang ◽  
Yani Xu ◽  
Yuanxiang Zhang
Keyword(s):  
Acoustic Waves ◽  
Vries Equation ◽  
Reductive Perturbation Method ◽  
Superthermal Electrons ◽  
Ion Plasma ◽  
Electron Positron ◽  
Electrons And Positrons ◽  
Ion Acoustic ◽  
De Vries ◽  
Superthermal Electrons And Positrons

Abstract In this work, we are concerned with the ion acoustic quasi-soliton in an electron-positron-ion plasma with superthermal electrons and positrons. By using the reductive perturbation method, the Korteweg-de Vries equation is derived from the governing equations of ion acoustic waves. An interesting soliton-cnoidal wave solution of the Korteweg-de Vries equation and its quasi-soliton behaviour are presented. The influence of electron superthermality, positron superthermality and positron concentration ratio on characteristics of the quasi-soliton is confirmed to be significant.

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