scholarly journals Dependence of the confinement time of an electron plasma on the magnetic field in a quadrupole Penning trap

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
B M Dyavappa ◽  
Durgesh Datar ◽  
Prakash ◽  
Sharath Ananthamurthy
Keyword(s):  
Magnetic Field ◽  
Penning Trap ◽  
Electron Plasma ◽  
Confinement Time ◽  
The Magnetic Field

Magnetic stabilization of transverse plasma instabilitiest

1971 ◽  
Vol 5 (3) ◽  
pp. 467-474 ◽  
Author(s):  
B. Buti ◽  
G. S. Lakhina
Keyword(s):  
Magnetic Field ◽  
Growth Rate ◽  
Cyclotron Frequency ◽  
Plasma Frequency ◽  
Electron Plasma ◽  
Wave Number ◽  
Uniform External Magnetic Field ◽  
Magnetic Stabilization ◽  
Streaming Velocity ◽  
The Magnetic Field

Waves, propagating transverse to the direction of the streaming of a plasma in the presence of a uniform external magnetic field, are unstable if the streaming exceeds a certain minimum value. The magnetic field reduces the growth rate of this instability, and also increases the value of the minimum streaming velocity, above which the system is unstable. The thermal motions in the plasma, however, tend to stabilize the system if the magnetic field is weak (i.e. , Ω being the electron cyclotron frequency, k the characteristic wave-number, and Vt the thermal velocity); but, in case of strong magnetic field (i.e. ), they increase the growth rate, provided (ωp being the electron plasma frequency).

Wave propagation in a moving plasma. Part 1. Wave propagation normal to the magnetic field and motion of the plasma along the magnetic field

1974 ◽  
Vol 11 (3) ◽  
pp. 389-395 ◽  
Author(s):  
D. N. Srivastava
Keyword(s):  
Magnetic Field ◽  
Wave Propagation ◽  
Dispersion Relation ◽  
Magnetic Fields ◽  
Plasma Frequency ◽  
Electron Plasma ◽  
Ordinary Wave ◽  
Moving Plasma ◽  
The Magnetic Field

The dispersion relation for a collisionless moving electron plasma, when the direction of motion is along the magnetic field, and that of the wave propagation normal to the magnetic field, is analysed. It is shown that in small magnetic fields the ordinary wave develops a new band of backward waves below the plasma frequency. When the frequency of the wave is higher than the plasma frequency, the effect of the motion of the plasma is identical to a deviation of the direction of propagation.

Nonlinear behaviour of a finite amplitude electron plasma wave - IV. Decay to ion cyclotron waves

1978 ◽  
Vol 363 (1715) ◽  
pp. 547-557
Keyword(s):  
Magnetic Field ◽  
Low Frequency ◽  
Electron Plasma ◽  
Finite Amplitude ◽  
Nonlinear Behaviour ◽  
Electron Plasma Wave ◽  
Ion Cyclotron Waves ◽  
Ion Cyclotron ◽  
Low Frequency Mode ◽  
The Magnetic Field

Plasma in a magnetic field displays low frequency modes near the ion cyclotron frequency for waves propagating at an angle to the magnetic field. These modes are only slightly modified in a bounded plasma, and therefore can be excited by nonlinear decay of electron plasma waves which also propagate at an angle to the magnetic field. The nonlinearly generated low frequency mode has been identified experimentally as an ion cyclotron wave by stimulating the decay. The resonant matching conditions have also been demonstrated.

Quantum fidelity evolution of Penning trap coherent states in an asymmetric open quantum system

2019 ◽  
Vol 19 (5&6) ◽  
pp. 413-423
Author(s):  
Somayeh Mehrabankar ◽  
Davood Afshar ◽  
Mojtaba Jafarpour
Keyword(s):  
Magnetic Field ◽  
Coherent States ◽  
Penning Trap ◽  
Open Systems ◽  
Thermal Bath ◽  
Initial State ◽  
Dissipation Coefficient ◽  
Open Systems Theory ◽  
The Magnetic Field ◽  
Quantum Fidelity

Assuming the Born-Markov approximation, we study the evolution of quantum fidelity in asymmetric systems consisting of two and three-mode independent oscillators interacting with a thermal bath. To this end, considering the Penning trap coherent states as the initial states of the system, we have studied the evolution of the quantum fidelity as a function of the parameters of the system, the environment and the initial state, in the framework of open systems theory. It is observed that fidelity is a decreasing function of the temperature and dissipation coefficient for both two and three-mode states. However, for the two-mode state, the fidelity is an oscillating function of time but a decreasing one in the low values of the magnetic field. In the case of a three-mode state, although the fidelity decreases with the magnetic field, dissipation coefficient and temperature, it is an irregular function of the asymmetric coefficient.

scholarly journals Current neutralization of ion beam rotating and propagating in plasma

1987 ◽  
Vol 5 (3) ◽  
pp. 481-493 ◽  
Author(s):  
Takayuki Aoki ◽  
Keishiro Niu
Keyword(s):  
Magnetic Field ◽  
Plasma Frequency ◽  
Ion Beam ◽  
Electron Plasma ◽  
Background Plasma ◽  
Plasma Current ◽  
Time Duration ◽  
Low Density Plasma ◽  
The Magnetic Field ◽  
Uniform Plasma

The current-neutralization fraction of a rotating and propagating light ion beam (LIB) injected into a low density plasma is investigated numerically. The beam space charge is essentially neutralized by a redistribution of the background plasma electrons in a time duration equal to the inverse of electron plasma frequency. When the density of the background plasma is comparable with that of the beam, incomplete current neutralization occurs because the strong magnetic field induced by the intense ion beam restricts the return plasma current.In the simulation, the ion beam and the background plasma are treated as the fluids coupled with Maxwell's equations and Ohm's law, including the effect of the magnetic field on electrical conductivity. The calculations assume that the ion beam is injected in an unsteady fashion into the uniform plasma. It is found that the return current strongly depends on the density of the background plasma. The beam deceleration and the acceleration of the beam head and tail are also considered.

Linear stability of Vlasov–Poisson electron plasma in crossed fields. Perturbations propagating parallel to the magnetic field

1988 ◽  
Vol 40 (3) ◽  
pp. 535-543 ◽  
Author(s):  
Hee-Jae Lee ◽  
D. J. Kaup ◽  
Gary E. Thomas
Keyword(s):  
Magnetic Field ◽  
Temperature Distribution ◽  
Dispersion Relation ◽  
Linear Stability ◽  
Electron Density ◽  
Electron Plasma ◽  
Eigenvalue Equation ◽  
Planar Magnetron ◽  
The Magnetic Field

It is shown that electrostatic Vlasov–Poisson perturbations that propagate parallel to the magnetic field in a planar magnetron are stable for both an isotropic and also for a particular anisotropic (Ty = 3Tx) temperature distribution. The inhomogeneity of the electron density is fully incorporated in the analysis. The proof makes use of only the dispersion relation of Trivelpiece–Gould type, without actually solving the eigenvalue equation. These results suggest, not unexpectedly, that these modes should be stable for all such anisotropic velocity distributions.

scholarly journals A Theory of Type I Solar Radio Bursts

1974 ◽  
Vol 57 ◽  
pp. 293-294 ◽  
Author(s):  
W. N.-C. Sy
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electromagnetic Radiation ◽  
Plasma Waves ◽  
Electron Plasma ◽  
Source Size ◽  
Plasma Radiation ◽  
Type I ◽  
Non Linear ◽  
The Magnetic Field

(Proc. Astron. Soc. Australia). A theory is developed to account for the observed properties of type I storm bursts in terms of plasma radiation – that is, electromagnetic radiation at the electron plasma frequency resulting from the non-linear scattering of electron plasma waves on plasma ions. Now the average brightness temperature of a type I source is greater than 109 K, or even higher if, because of coronal scattering, the apparent source size is larger than the true source size. For brightness temperatures as high as 109 K the non-linear scattering must be of the induced kind in which electromagnetic radiation below the frequency of the electron plasma waves is amplified. For such radiation to be strongly circularly polarized in the o-mode, as observed in type I bursts, requires that the amplification be more effective in the o-mode than in the x-mode (Figure 1). This is found to be so for plasma waves excited by electrons travelling parallel to the magnetic field. The electric field of the plasma waves is then also parallel to the magnetic field. The non-linear scattering is more efficient for that magnetoionic mode which has the greater component of electric field in the same direction. This mode is the o-mode.

Wave propagation in a moving plasma: motion and wave propagation normal to the magnetic field

1973 ◽  
Vol 10 (2) ◽  
pp. 197-202
Author(s):  
D. N. Srivastava
Keyword(s):  
Magnetic Field ◽  
Wave Propagation ◽  
Dispersion Relation ◽  
Electron Plasma ◽  
Extraordinary Wave ◽  
Ordinary Wave ◽  
Phase Velocities ◽  
Small Phase ◽  
Moving Plasma ◽  
The Magnetic Field

The dispersion relation for a collisionless moving electron plasma when the directions of motion and wave propagation are normal to the magnetic field is analyzed. It is shown that the ordinary wave remains unaffected, but the extraordinary wave shows a different behaviour, especially at small phase velocities. It has different cut-off frequencies, propagates for all frequencies from zero to infinity, changes the sense of polarization accompanied by anomalous dispersion and does not show any resonance.

Frequency doubling of extraordinary wave

1986 ◽  
Vol 35 (1) ◽  
pp. 125-132 ◽  
Author(s):  
V. M. Čadež ◽  
D. Jovanović
Keyword(s):  
Magnetic Field ◽  
Pump Wave ◽  
Second Harmonic ◽  
Frequency Doubling ◽  
Electron Plasma ◽  
Extraordinary Wave ◽  
Slab Thickness ◽  
Phase Synchronism ◽  
Efficiency Parameter ◽  
The Magnetic Field

Second-harmonic generation of an extraordinary wave is investigated in the domain of phase synchronism with the pump wave. The conversion efficiency parameter is calculated for various values of the magnetic field, electron plasma density, angle of propagation and slab thickness.

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