Basis of the quasi-steady plasma accelerator theory in the presence of a longitudinal magnetic field

AbstractThe analytic and numerical approaches to the investigation of the two-dimensional steady-state plasma flows are analyzed and compared with reference to a plasma accelerator channel in the presence of a longitudinal magnetic field. The present study continues a cycle of research into the plasma flows in the coaxial channels with the traditional azimuthal magnetic field. The additional longitudinal field opens new possibilities for controlling the dynamic processes and achieving the transonic flows. The research is based on the magnetohydrodynamic equations.

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The influence of resistivity gradients on shock conditions for a Petschek reconnection geometry

Annales Geophysicae ◽

10.5194/angeo-34-421-2016 ◽

2016 ◽

Vol 34 (4) ◽

pp. 421-425

Author(s):

Christian Nabert ◽

Karl-Heinz Glassmeier

Keyword(s):

Magnetic Field ◽

Necessary Conditions ◽

The Other ◽

Diffusion Region ◽

Two Dimensional ◽

Characteristic Velocity ◽

Magnetohydrodynamic Equations ◽

One Dimensional ◽

The Magnetic Field ◽

Alfven Velocity

Abstract. Shock waves can strongly influence magnetic reconnection as seen by the slow shocks attached to the diffusion region in Petschek reconnection. We derive necessary conditions for such shocks in a nonuniform resistive magnetohydrodynamic plasma and discuss them with respect to the slow shocks in Petschek reconnection. Expressions for the spatial variation of the velocity and the magnetic field are derived by rearranging terms of the resistive magnetohydrodynamic equations without solving them. These expressions contain removable singularities if the flow velocity of the plasma equals a certain characteristic velocity depending on the other flow quantities. Such a singularity can be related to the strong spatial variations across a shock. In contrast to the analysis of Rankine–Hugoniot relations, the investigation of these singularities allows us to take the finite resistivity into account. Starting from considering perpendicular shocks in a simplified one-dimensional geometry to introduce the approach, shock conditions for a more general two-dimensional situation are derived. Then the latter relations are limited to an incompressible plasma to consider the subcritical slow shocks of Petschek reconnection. A gradient of the resistivity significantly modifies the characteristic velocity of wave propagation. The corresponding relations show that a gradient of the resistivity can lower the characteristic Alfvén velocity to an effective Alfvén velocity. This can strongly impact the conditions for shocks in a Petschek reconnection geometry.

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Compressible plasma flows in the QSPA in the presence of strong longitudinal magnetic field

Keldysh Institute Preprints ◽

10.20948/prepr-2018-217 ◽

2018 ◽

pp. 1-20

Author(s):

Andrey Nikolaevich Kozlov

Keyword(s):

Magnetic Field ◽

Longitudinal Magnetic Field ◽

Plasma Flows ◽

Compressible Plasma

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Plasma Flow Peculiarities in Accelerator Channel with Longitudinal Magnetic Field

37th AIAA Plasmadynamics and Lasers Conference ◽

10.2514/6.2006-3564 ◽

2006 ◽

Cited By ~ 1

Author(s):

Andrey Kozlov

Keyword(s):

Magnetic Field ◽

Plasma Flow ◽

Longitudinal Magnetic Field ◽

Accelerator Channel

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Two-fluid magnetohydrodynamic model of plasma flows in a quasi-steady-state accelerator with a longitudinal magnetic field

Journal of Applied Mechanics and Technical Physics ◽

10.1007/s10808-009-0053-7 ◽

2009 ◽

Vol 50 (3) ◽

pp. 396-405 ◽

Cited By ~ 11

Author(s):

A. N. Kozlov

Keyword(s):

Magnetic Field ◽

Steady State ◽

Longitudinal Magnetic Field ◽

Quasi Steady State ◽

Plasma Flows ◽

Magnetohydrodynamic Model ◽

Two Fluid

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The instability of a pinched fluid with a longitudinal magnetic field

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1958.0079 ◽

1958 ◽

Vol 245 (1241) ◽

pp. 222-237 ◽

Cited By ~ 86

Keyword(s):

Magnetic Field ◽

Longitudinal Magnetic Field ◽

Short Wave ◽

Longitudinal Field ◽

Plasma Equilibrium ◽

Azimuthal Magnetic Field ◽

Long Wave ◽

Pinched Plasma ◽

Pinch Current ◽

The Stability

The stability of a pinched plasma equilibrium with a longitudinal magnetic field superimposed on the characteristic azimuthal magnetic field of the pinch current is studied theoretically. The linearized solutions are developed as helical perturbations of the plasma surface, and the behaviour of these is given for the different cases of uniform longitudinal, longitudinal field zero inside the plasma, and for helices of the same and opposite sense to the helix which describes the total magnetic field. Approximately, the conclusions are: that the longitudinal field has the effect of stabilizing short-wave perturbations, but that some long-wave perturbations remain unstable no matter how large the externally imposed longitudinal magnetic field.

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Improvement of ion acceleration in radiation pressure acceleration regime by using an external strong magnetic field

Laser and Particle Beams ◽

10.1017/s026303461900034x ◽

2019 ◽

Vol 37 (2) ◽

pp. 217-222 ◽

Cited By ~ 4

Author(s):

H. Cheng ◽

L. H. Cao ◽

J. X. Gong ◽

R. Xie ◽

C. Y. Zheng ◽

...

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Laser Pulse ◽

Radiation Pressure ◽

Longitudinal Magnetic Field ◽

Ponderomotive Force ◽

Two Dimensional ◽

Particle In Cell ◽

Combined Action ◽

The Magnetic Field

AbstractTwo-dimensional particle-in-cell (PIC) simulations have been used to investigate the interaction between a laser pulse and a foil exposed to an external strong longitudinal magnetic field. Compared with that in the absence of the external magnetic field, the divergence of proton with the magnetic field in radiation pressure acceleration (RPA) regimes has improved remarkably due to the restriction of the electron transverse expansion. During the RPA process, the foil develops into a typical bubble-like shape resulting from the combined action of transversal ponderomotive force and instabilities. However, the foil prefers to be in a cone-like shape by using the magnetic field. The dependence of proton divergence on the strength of magnetic field has been studied, and an optimal magnetic field of nearly 60 kT is achieved in these simulations.

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