27.—The Quantum Theory of the Klystron and the Modulation of Electron Beams at Optical Frequencies

1974 ◽  
Vol 71 (4) ◽  
pp. 305-321
Author(s):  
P. S. Farago ◽  
R. M. Sillitto
Keyword(s):  
Electron Beam ◽  
Single Photon ◽  
Electron Beams ◽  
Modulation Frequency ◽  
Periodic Variation ◽  
Mechanical Effect ◽  
Optical Frequency ◽  
Total Electron ◽  
Quantum Mechanical Effect ◽  
The Individual

SynopsisThe relationship between the modulation of electron beams at optical frequencies (the Schwarz-Hora effect) and at microwave frequencies is discussed. At optical frequencies the interaction between the modulating field and the electron beam must be described quantum mechanically, although the field itself may be described classically; in the microwave case the process may be described entirely classically. The interaction modifies the state functions of the individual electrons, but the observable modulation of the total electron beam results from the coherence of the modulating field. The main features of the Schwarz-Hora effect result from ‘single photon’ processes, but the beam modulation in the klystron is a ‘multi-photon’ process.The exponential decay of the depth of modulation with distance from the interaction region, observable in the optical frequency case but not in the klystron, is not an inherently quantal effect. The periodic variation of the depth of modulation with distance along the beam, observed in the optical frequency case, is an essentially quantum mechanical effect, and is different, in its origins and in its dependence on the modulation frequency, from the space-charge waves which are observed on a klystron beam.

Materials for Electron Beam Information Storage

1969 ◽  
Vol 27 ◽  
pp. 152-153 ◽  
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.

Energy Distribution in Electron Beams

1972 ◽  
Vol 30 ◽  
pp. 568-569
Author(s):  
Tamotsu Ohno
Keyword(s):  
Electron Beam ◽  
Energy Distribution ◽  
Cross Section ◽  
Integral Curve ◽  
Electron Beams ◽  
Electron Gun ◽  
Angular Divergence ◽  
Apparent Increase ◽  
Integral Width ◽  
The Cross

The energy distribution in an electron; beam from an electron gun provided with a biased Wehnelt cylinder was measured by a retarding potential analyser. All the measurements were carried out with a beam of small angular divergence (<3xl0-4 rad) to eliminate the apparent increase of energy width as pointed out by Ichinokawa.The cross section of the beam from a gun with a tungsten hairpin cathode varies as shown in Fig.1a with the bias voltage Vg. The central part of the beam was analysed. An example of the integral curve as well as the energy spectrum is shown in Fig.2. The integral width of the spectrum ΔEi varies with Vg as shown in Fig.1b The width ΔEi is smaller than the Maxwellian width near the cut-off. As |Vg| is decreased, ΔEi increases beyond the Maxwellian width, reaches a maximum and then decreases. Note that the cross section of the beam enlarges with decreasing |Vg|.

scholarly journals Supershort avalanche electron beam generation in gases

2008 ◽  
Vol 26 (4) ◽  
pp. 605-617 ◽  
Author(s):  
V.F. Tarasenko ◽  
E.H. Baksht ◽  
A.G. Burachenko ◽  
I.D. Kostyrya ◽  
M.I. Lomaev ◽  
...  
Keyword(s):  
High Pressure ◽  
Electron Beam ◽  
Atmospheric Pressure ◽  
Electron Beams ◽  
Solid Angle ◽  
Generation Mechanism ◽  
Full Width ◽  
Half Maximum ◽  
Electron Beam Pulse ◽  
Supershort Avalanche Electron Beam

AbstractThis paper reports on the properties of a supershort avalanche electron beam generated in the air or other gases under atmospheric pressure and gives the analysis of a generation mechanism of supershort avalanche electron beam, as well as methods of such electron beams registration. It is reported that in the air under the pressure of 1 atm, a supershort (<100 ps) avalanche electron beam is formed in the solid angle more than 2π steradian. The electron beam has been obtained behind a 45 µm thick Al-Be foil in SF6 and Xe under the pressure of 2 atm, and in He, under the pressure of about 15 atm. It is shown that in SF6 under the high pressure (>1 atm) duration (full width at half maximum) of supershort avalanche electron beam pulse is about 150 ps.

scholarly journals Electron beam relaxation in inhomogeneous plasmas

2013 ◽  
Vol 31 (8) ◽  
pp. 1379-1385 ◽  
Author(s):  
A. Voshchepynets ◽  
V. Krasnoselskikh
Keyword(s):  
Electron Beam ◽  
Beam Energy ◽  
Electron Beams ◽  
Inhomogeneous Plasma ◽  
Density Fluctuations ◽  
Langmuir Waves ◽  
Wave Trapping ◽  
Beam Plasma ◽  
Beam Plasma Instability ◽  
Accelerated Particles

Abstract. In this work, we studied the effects of background plasma density fluctuations on the relaxation of electron beams. For the study, we assumed that the level of fluctuations was so high that the majority of Langmuir waves generated as a result of beam-plasma instability were trapped inside density depletions. The system can be considered as a good model for describing beam-plasma interactions in the solar wind. Here we show that due to the effect of wave trapping, beam relaxation slows significantly. As a result, the length of relaxation for the electron beam in such an inhomogeneous plasma is much longer than in a homogeneous plasma. Additionally, for sufficiently narrow beams, the process of relaxation is accompanied by transformation of significant part of the beam kinetic energy to energy of accelerated particles. They form the tail of the distribution and can carry up to 50% of the initial beam energy flux.

scholarly journals Response of chromospheric lines to different periodic non-thermal electron beams

2015 ◽  
Vol 11 (S320) ◽  
pp. 239-242
Author(s):  
Jianxia Cheng ◽  
Mingde Ding
Keyword(s):  
Electron Beam ◽  
Solar Flares ◽  
Local Thermodynamic Equilibrium ◽  
Response Times ◽  
Electron Beams ◽  
Lower Atmosphere ◽  
Mass Motion ◽  
Thermal Electron ◽  
Hydrodynamic Simulations ◽  
Beam Injection

AbstractSolar flares produce radiations in very broad wavelengths. Spectra can supply us abundant information about the local plasma, such as temperature, density, mass motion and so on. Strong chromospheric lines, like the most studied Hα and Ca II 8542 Å lines are formed under conditions of departures from local thermodynamic equilibrium in the lower atmosphere subject to flare heating. Understanding how these lines are formed is very useful for us to correctly interpret the observations. In this paper, we try to figure out the response of chromospheric lines heated by different periodic non-thermal electron beams. Our results are based on radiative hydrodynamic simulations. We vary the periods of electron beam injection from 1.25 s to 20 s. We compare the response times to different heating parameters. Possible explanations are discussed.

scholarly journals Detection of oscillatory solutions in a vacuum diode with total electron reflection

2021 ◽  
Vol 2103 (1) ◽  
pp. 012205
Author(s):  
V I Kuznetsov ◽  
IK Morozov
Keyword(s):  
Electron Beam ◽  
Electric Field ◽  
Vacuum Diode ◽  
Boundary Line ◽  
Electrode Gap ◽  
Oscillatory Solutions ◽  
Total Electron ◽  
Electron Reflection ◽  
Instability Development ◽  
Non Linear

Abstract Stability features of steady-state solutions for a vacuum diode with complete deceleration of electron beam is studied. A boundary line on the (inter-electrode gap, external voltage)-plane separating stable solutions from unstable ones is built up. An instability development is shown to end in a state with non-linear oscillations of the electric field but with no virtual cathode in a plasma. Existence of non-linear oscillations of the electric field in a vacuum diode with total reflection of an electron beam points out that such a diode can be a basis to create microwave generator.

scholarly journals Electron beam control using experimentally measured transport matrices

1994 ◽  
Vol 12 (1) ◽  
pp. 17-21 ◽  
Author(s):  
C.B. McKee ◽  
John M.J. Madey
Keyword(s):  
Spatial Distribution ◽  
Electron Beam ◽  
Electron Accelerator ◽  
Electron Beams ◽  
Transport Systems ◽  
Evoked Responses ◽  
Free Electron Lasers ◽  
High Brightness ◽  
Electron Accelerators

Free electron lasers (FELs) place very stringent requirements on the quality of electron beams. Present techniques for commissioning and operating electron accelerators may not be optimized to produce the high brightness beams needed. Therefore, it is proposed to minimize the beamline errors in electron accelerator transport systems by minimizing the deviations between the experimentally measured and design transport matrices of each beamline section. The transport matrix for each section is measured using evoked responses. In addition, the transverse phase space of the beam is reconstructed by measuring the spatial distribution of the electrons at a number of different betatron phases and applying tomographic techniques developed for medical imaging.

Electron beam lithography for high density meta fish scale operational at optical frequency

2009 ◽  
Vol 86 (4-6) ◽  
pp. 1081-1084 ◽  
Author(s):  
Yifang Chen ◽  
Alexander S. Schwanecke ◽  
V.A. Fedotov ◽  
V.V. Khardikov ◽  
P.L. Mladyonov ◽  
...  
Keyword(s):  
Electron Beam ◽  
Electron Beam Lithography ◽  
High Density ◽  
Optical Frequency ◽  
Fish Scale
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