Condition for magnetic insulation of the electron beam in 
a rod-pinch diode

A condition for the transition of the electron beam produced in a coaxial rod-pinch diode to the mode of magnetic insulation has been established from the law of conservation of particle and field momentum fluxes. The magnetic field of the external current has been shown to contribute twice as much to magnetic insulation of the beam as the magnetic field of the electron beam self-current. Based on the relations derived, a model has been constructed for magnetic insulation of the electron flow in high-current rod-pinch diodes, which are used for radiography of high speed phenomena. The obtained theoretical results agree well with the results of numerical calculations and with experimental data gained at the Naval Research Laboratory (USA).

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MULTI-PURPOSE MODES OF FORMATION OF ELECTRON BEAMS IN THE CYLINDRICAL MAGNETIC FIELD OF THE MAGNETRON GUN

10.46813/2021-133-045 ◽

2021 ◽

pp. 45-49

Author(s):

A.S. Mazmanishvili ◽

N.G. Reshetnyak

Keyword(s):

Magnetic Field ◽

Experimental Data ◽

Electron Beam ◽

Electron Beams ◽

Electron Flow ◽

Axial Direction ◽

Beam Diameter ◽

Transport Channel ◽

Comparison Of The Results ◽

The Magnetic Field

The results of the study on the formation of electron beams by the magnetron gun at various configurations of the magnetic field in the beam transport channel are presented. A technique for modeling the processes of formation of electron flows and control of the distribution of beams by collimation is presented. Numerical simulation of the dynamics of electron beams in the magnetic field of the gun for its various configurations has been carried out. Experimental data on the transportation and collimation of electron beams are presented. The possibility of stable formation of an electron beam in the axial direction during its transportation is shown. Imprints of the collimated electron beam were obtained on metal targets. The possibility of controlling the beam diameter by varying the magnetic field is shown. Comparison of the results of numerical modeling and experimental data on the motion and collimation of the tubular electron flow is carried out.

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Emission Features and Structure of an Electron Beam versus Gas Pressure and Magnetic Field in a Cold-Cathode Coaxial Diode

Electronics ◽

10.3390/electronics11020248 ◽

2022 ◽

Vol 11 (2) ◽

pp. 248

Author(s):

Gennady Mesyats ◽

Vladislav Rostov ◽

Konstantin Sharypov ◽

Valery Shpak ◽

Sergey Shunailov ◽

...

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Runaway Electrons ◽

High Current ◽

Emission Mechanism ◽

Explosive Emission ◽

Fast Electrons ◽

Atmospheric Air ◽

Emission Surface ◽

The Magnetic Field

The structure of the emission surface of a cold tubular cathode and electron beam was investigated as a function of the magnetic field in the coaxial diode of the high-current accelerator. The runaway mode of magnetized electrons in atmospheric air enabled registering the instantaneous structure of activated field-emission centers at the cathode edge. The region of air pressure (about 3 Torr) was determined experimentally and via analysis, where the explosive emission mechanism of the appearance of fast electrons with energies above 100 keV is replaced by the runaway electrons in a gas.

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DYNAMICS OF AN ELECTRON BEAM FORMED BY MAGNETRON GUN WITH THE SECONDARY EMISSION CATHODE IN THE DECLINING MAGNETIC FIELD OF SOLENOID: EXPERIMENT AND SIMULATION

Bulletin of National Technical University KhPI Series System Analysis Control and Information Technologies ◽

10.20998/2079-0023.2021.02.05 ◽

2021 ◽

pp. 27-34

Author(s):

Oleksandr Mazmanishvili ◽

Nikolay Reshetnyak ◽

Ganna Sydorenko

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Permanent Magnets ◽

Initial Conditions ◽

Electron Flow ◽

Beam Current ◽

Secondary Emission ◽

Stray Field ◽

The Magnetic Field ◽

Emission Cathode

The article presents the results of research and calculations on the formation of a radial electron beam by a magnetron gun with a secondary emission cathode in the electron energy range 35...65 keV and measuring its parameters during transportation in the total decreasing magnetic field of thesolenoid and the stray field of permanent magnets. The beam was transported in a system consisting of copper rings with an inner diameter of 66 mm,located at a distance of 85 mm from the exit of the magnetron gun. The dependence of the beam current on the amplitude and gradient of the fielddecay has been studied. The studies carried out have shown the possibility of stable formation of a radial electron beam with an energy of tens of keVin the decreasing magnetic field of the solenoid. By optimizing the distribution of the magnetic field (created by the solenoid and ring magnets) and itsdecay gradient, it is possible to achieve an increase in the incident of electrons on one ring (up to ~72% of the beam current). On the basis of themathematical model of the movement of the electron flow, a software tool has been synthesized that makes it possible to obtain and interpret thecharacteristics of the resulting flows. The obtained numerical dependences are in satisfactory agreement with the experimental results for a magneticfield with a large decay gradient. Various configurations of the magnetic field are considered. Solutions to the direct problem of modeling electrontrajectories for given initial conditions and parameters are obtained. Various configurations of the magnetic field are considered. It is shown that forthe selected initial conditions for the electron beam and the distributions of the longitudinal magnetic field along the axis of the gun and the transportchannel, the electron flux falls on a vertical section, the length of which is on the order of a millimeter. Thus, by changing the amplitude anddistribution of the magnetic field, it is possible to control the current in the radial direction along the length of the pipe, and, therefore, the place of theelectron irradiation.

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Simulation of propagating a proton beam in a reactor

Laser and Particle Beams ◽

10.1017/s0263034600010855 ◽

1997 ◽

Vol 15 (1) ◽

pp. 151-165 ◽

Cited By ~ 3

Author(s):

K. Niu

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Proton Beam ◽

High Speed ◽

Electrostatic Force ◽

Ion Beam ◽

Leading Edge ◽

Small Radius ◽

Field Energy ◽

The Magnetic Field

One of the difficulties of light ion beam fusion is to propagate the beam in the reactor cavity and to focus the beam on the target. The light ion beam has some local divergence angle because there are several causes for divergence at the diode. The ion beam propagates with a speed of one tenth of light speed. With this high speed, the leading edge of the ion beam cannot be charge-neutralized due to the delay of neutralization by the inertia of thermal electrons in the background plasma. The electrostatic force induced by this mechanism at the leading edge causes the beam divergence during propagation. To confine the beam in a small radius during propagation, the magnetic field must play a role. Here the electron beam is proposed to be launched simultaneously with the launch of a proton beam. If the electron beam has the excess current, the beam induces the magnetic field in the negative azimuthal direction, which confines the ion beam in a small radius by the electrostatic field, as well as the electron beam by the Lorentz force. The metal guide around the beam path helps the beam confinement and reduces the total amount of magnetic field energy induced by the electron current. Simulation shows that the proton beam with the comoving electron beam propagates in a small radius confined in the metal guide.

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LONGITUDINAL TRAP OF ELECTRON BEAM IN POTENTIAL PIT MAGNETIC SOLENOIDAL FIELD

Bulletin of National Technical University KhPI Series System Analysis Control and Information Technologies ◽

10.20998/2079-0023.2021.01.10 ◽

2021 ◽

pp. 62-66

Author(s):

Oleksandr Mazmanishvili ◽

Nikolay Reshetnyak

Keyword(s):

Magnetic Field ◽

Numerical Simulation ◽

Electron Beam ◽

Electron Flow ◽

Three Dimensional ◽

Hamiltonian Formalism ◽

Polar Angle ◽

Longitudinal Motion ◽

Gradient Magnetic Field ◽

The Magnetic Field

A two-mode cylindrical magnetic field is considered, the potential of which has a minimum. The object of this work is the study of the parameters of an electron beam when it moves in a solenoid field with the longitudinal trap formed by the magnetic field, and the construction of the computational model of the motion of an electron beam. The problem is posed of the stability of the motion of electrons in such solenoid magnetic field. The possibility of obtaining oscillatory modes of particle motion has been studied. It was found that for oscillations of particles with an energy of tens of kiloelectronvolts in the potential well in a well, the field with the amplitude of tens of thousands of Oersteds is required. For the solenoid magnetic field of the solenoid, the formation of electron beam with an energy of 55 keV in the longitudinal and radial directions during its transportation is studied. A section of a magnetron gun was used as the physical object. One possible direction is to combine the two matched magnetic systems of the gun to create the potential magnetic field well. It is shown that, for the chosen conditions, the motion of electrons can be associated with the model of three-dimensional oscillations. In this work, on the basis of the Hamiltonian formalism of the motion of electrons in a magnetic field and an algorithm for numerically finding solutions to the differential equations of dynamics, a software tool is constructed that allows one to obtain arrays of values of particle trajectories in the volume. The use of the software made it possible to simulate the main dependences of the motion of the electron beam in a given two-mode solenoid magnetic field. The results of numerical simulation of electron trajectories in the gradient magnetic field with the point secondary emission cathode located in the middle of the system are presented. The formation of the beam with energy of 55 keV in the radial and longitudinal directions during its transportation in a solenoid magnetic field with a large gradient is considered. For significant time intervals, the possibility of three-dimensional oscillations is shown and the operating modes of the magnetic system are obtained, in which the particle undergoes stable three-dimensional oscillations. The influence of the initial conditions during emission on the occurrence of the reciprocating oscillatory effect has been studied. It is shown that for a given electron energy and fixed magnetic field, the parameter that determines the reflection of a particle, is the polar angle of entry relative to the axis of the cylindrical magnetic field. The dependence of the formation of the final distribution of particles on the amplitude and gradient of the magnetic field along the axis of the system is investigated. The results of numerical simulation on the motion of the electron flow are presented. The characteristics of the resulting electron beam are considered on the basis of a model of electron flow motion. The obtained simulation results show that it is possible to establish the phenomenon of oscillatory-return longitudinal motion under experimental conditions. Keywords: electron beam, magnetron gun, three-dimensional oscillations, electron dynamics, gradient magnetic field, mathematical modeling.

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SIMULATION OF THE COMPENSATION OF A HIGH-CURRENT ION BEAM BY AN ELECTRON BEAM IN A CUSP MAGNETIC SYSTEM

10.46813/2021-134-122 ◽

2021 ◽

pp. 122-127

Author(s):

I.N. Onishchenko ◽

O.V. Fedorovskaya

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Space Charge ◽

Longitudinal Magnetic Field ◽

Ion Beam ◽

Zero Magnetic Field ◽

High Current ◽

Field Lines ◽

Dynamics Of Particles ◽

The Magnetic Field

The results of 2.5D-simulation of the dynamics of particles of a high-current ion beam moving in a magnetic field of acute-angled geometry (cusp), compensated in charge and current by an electron beam injected along the radius onto the axis from the periphery, uniformly in azimuth, are presented. The influence of own space charge fields and polarization fields on the dynamics of ions is clarified. It is shown that at high densities of the electron and ion beams, the electron beam injected into the cusp together with the ion beam, moving along the magnetic field lines, drags the ion beam away from the axis to the periphery into the region of zero magnetic field. At the exit from the cusp, the electron beam injected along the radius onto the axis drifts along the axis in a uniform magnetic field, while the ion beam performs oscillatory motion by radius in the crossed the electric field of the electron beam space charge and the longitudinal magnetic field.

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Materials for Electron Beam Information Storage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062671 ◽

1969 ◽

Vol 27 ◽

pp. 152-153 ◽

Cited By ~ 1

Author(s):

D. E. Speliotis

Keyword(s):

Magnetic Field ◽

Electron Beam ◽

Recent Literature ◽

Electron Beams ◽

Information Storage ◽

The Subject ◽

The Magnetic Field

The interaction of electron beams with a large variety of materials for information storage has been the subject of numerous proposals and studies in the recent literature. The materials range from photographic to thermoplastic and magnetic, and the interactions with the electron beam for writing and reading the information utilize the energy, or the current, or even the magnetic field associated with the electron beam.

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Experimental investigation and optimization on field shaper structure parameters in magnetic pulse welding

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211014846 ◽

2021 ◽

pp. 095440542110148

Author(s):

Yingzi Chen ◽

Zhiyuan Yang ◽

Wenxiong Peng ◽

Huaiqing Zhang

Keyword(s):

Magnetic Field ◽

High Speed ◽

Light Metal ◽

Magnetic Pulse ◽

Cross Sectional ◽

Magnetic Pulse Welding ◽

Pulse Welding ◽

Sectional Shape ◽

Welding System ◽

The Magnetic Field

Magnetic pulse welding is a high-speed welding technology, which is suitable for welding light metal materials. In the magnetic pulse welding system, the field shaper can increase the service life of the coil and contribute to concentrating the magnetic field in the welding area. Therefore, optimizing the structure of the field shaper can effectively improve the efficiency of the system. This paper analyzed the influence of cross-sectional shape and inner angle of the field shaper on the ability of concentrating magnetic field via COMSOL software. The structural strength of various field shapers was also analyzed in ABAQUS. Simulation results show that the inner edge of the field shaper directly affects the deformation and welding effect of the tube. So, a new shape of field shaper was proposed and the experimental results prove that the new field shaper has better performance than the conventional field shaper.

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Theoretical Investigation of the Shubnikov-de Haas Magnetoresistance Oscillations in a Quantum well under the Influence of Confined Acoustic Phonons

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.783.1 ◽

2018 ◽

Vol 783 ◽

pp. 1-11

Author(s):

Le Thai Hung ◽

Pham Ngoc Thang ◽

Nguyen Quang Bau

Keyword(s):

Magnetic Field ◽

Quantum Well ◽

Phonon Confinement ◽

Acoustic Phonons ◽

Magnetic Impedance ◽

Magnetoresistance Oscillations ◽

The Magnetic Field ◽

Amplitude Decrease ◽

Theoretical Results ◽

Phonon Confinement Effect

The Shubnikov – de Haas magnetoresistance oscillations in the Quantum well (QW) under the influence of confined acoustic phonons, The theoretical results show that the conductivity tensor, the complex magnetic impedance of the magnetic field, the frequency, the amplitude of the laser radiation, the QW width, the temperature of the system and especially the quantum index m characterizes the confinement of the phonon. The amplitude of the oscillations of the Shubnikov-de Haas impedance decreases with the increase of the influence of the confined acoustic phonons. The results for bulk phonons in a QW could be achieved, when m goes to zero. We has been compared with other studies when perform the numerical calculations are also achieved for the GaAs/AlGaAs in the QW. Results show that The Shubnikov-de Haas magnetoresistance oscillations amplitude decrease when phonon confinement effect increasing and when width L of the QW increases to a certain value, The Shubnikov – de Haas magnetoresistance oscillations amplitude completely disappears can not be observed.

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