SHORT PULSE ELECTRON LINAC WITH FULL BEAM LOADING COMPENSATION

Acceleration of intense short-pulsed electron beams in transient mode with energy spread about a few tenths of a percent is the actual problem for RF linacs, in an instance, for an electron injector of a storage ring. In this work we study both analytically and numerically unsteady self-consistent beam dynamics in the one section RF linac fed from SLED. For compensation of the transient beam loading, resulting in beam energy spread, a method of a beam delay with respect to RF pulse is consider. In order to increase efficiency of this method we choose a homogenous dick-loaded waveguide with π/2 phase advance as an accelerating structure that characterized by the minimal frequency dispersion of group velocity. The preliminary results show that the full beam loading compensation is possible for the 1.2 A beam at its acceleration up to 60 MeV during 50 ns.

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Control of electron beam energy-spread by beam loading effects in a laser-plasma accelerator

Plasma Physics and Controlled Fusion ◽

10.1088/1361-6587/ab7c50 ◽

2020 ◽

Vol 62 (5) ◽

pp. 055004 ◽

Cited By ~ 1

Author(s):

Guangyu Li ◽

Quratul Ain ◽

Song Li ◽

Muhammad Saeed ◽

Daniel Papp ◽

...

Keyword(s):

Electron Beam ◽

Laser Plasma ◽

Beam Energy ◽

Plasma Accelerator ◽

Energy Spread ◽

Electron Beam Energy ◽

Beam Loading ◽

Loading Effects ◽

Laser Plasma Accelerator

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On b.c.c. 3He, a Highly Anharmonic Crystal

Canadian Journal of Physics ◽

10.1139/p71-091 ◽

1971 ◽

Vol 49 (6) ◽

pp. 761-775 ◽

Cited By ~ 31

Author(s):

H. R. Glyde

Keyword(s):

Elastic Constants ◽

Lattice Dynamics ◽

Phonon Frequency ◽

Frequency Dispersion ◽

Anharmonic Crystal ◽

Self Consistent ◽

Anharmonic Term ◽

Single Method ◽

The One ◽

Anharmonic Crystals

The self consistent (SC) theory of lattice dynamics for highly anharmonic crystals is derived via expansion and selected re-summation of the one phonon Green function. Since perturbation treatments of weakly anharmonic crystals use the same expansion, the two cases can then be viewed as variations in a single method. The SC theory to lowest (SCH) and second (SC2) order and a re-order potential power series in which each coefficient appears averaged over the vibrational motion is derived.The SCH theory with the leading correction in the new series, the cubic anharmonic term, is applied to b.c.c. 3He. Phonon frequency dispersion curves, lifetimes, sound velocities, and elastic constants are computed. The phonons are well defined and the elastic constants and isotropy agree quite well with experiment. Although the cubic correction is significant, it suggests that the re-ordered series converges.

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The Rules for the Lattice Rotation Accompanying Slip as Derived From a Self-Consistent Model

Textures and Microstructures ◽

10.1155/tsm.31.217 ◽

1999 ◽

Vol 31 (4) ◽

pp. 217-230 ◽

Cited By ~ 18

Author(s):

R. A. Lebensohn ◽

T. Leffers

Keyword(s):

Solid Mechanics ◽

Grain Shape ◽

Rolling Plane ◽

Lattice Rotation ◽

Consistent Model ◽

Plane Strain Deformation ◽

Self Consistent ◽

The One ◽

Equiaxed Grains ◽

Very High

The rules for the lattice rotation during rolling (plane strain) deformation of fcc polycrystals are studied with a viscoplastic self-consistent model. Very high values of the ratesensitivity exponent are used in order to establish Sachs-type conditions with large local deviations from the macroscopic strain. The lattice rotation depends on the grain shape. For equiaxed grains the lattice rotation follows the MA rule, which is the one normally used in solid mechanics. For elongated and flat grains the lattice rotation follows a different rule, the PSA rule. In the standard version the model performs a transition from MA to PSA with increasing strain. There is avery clear difference between the textures resulting from the two different rules. MA leads to a copper-type texture, and PSA leads to a brass-type texture.

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Many-body Green functions in nuclear physics

International Journal of Modern Physics E ◽

10.1142/s0218301317400250 ◽

2017 ◽

Vol 26 (01n02) ◽

pp. 1740025 ◽

Cited By ~ 1

Author(s):

J. Speth ◽

N. Lyutorovich

Keyword(s):

Nuclear Physics ◽

Green Functions ◽

Many Body ◽

General Applicability ◽

Pair Correlations ◽

Self Consistent ◽

The Many ◽

The One ◽

General Relations ◽

Three Body

Many-body Green functions are a very efficient formulation of the many-body problem. We review the application of this method to nuclear physics problems. The formulas which can be derived are of general applicability, e.g., in self-consistent as well as in nonself-consistent calculations. With the help of the Landau renormalization, one obtains relations without any approximations. This allows to apply conservation laws which lead to important general relations. We investigate the one-body and two-body Green functions as well as the three-body Green function and discuss their connection to nuclear observables. The generalization to systems with pair correlations are also presented. Numerical examples are compared with experimental data.

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Spin-Wave Spectrum in the Sinusoidal Superlattice with Amplitude and Phase Inhomogeneities

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.215.385 ◽

2014 ◽

Vol 215 ◽

pp. 385-388

Author(s):

Valter A. Ignatchenko ◽

Denis S. Tsikalov

Keyword(s):

Spin Wave ◽

Density Of States ◽

Wave Spectrum ◽

The Self ◽

One Dimensional ◽

Consistent Approximation ◽

Self Consistent ◽

Greens Function ◽

The One ◽

Spin Wave Spectrum

Effects of both the phase and the amplitude inhomogeneities of different dimensionalities on the Greens function and on the one-dimensional density of states of spin waves in the sinusoidal superlattice have been studied. Processes of multiple scattering of waves from inhomogeneities have been taken into account in the self-consistent approximation.

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On Peculiarities of Betatron Oscillations of Accelerated Electron Bunches in Capillary Waveguides

Laser and Particle Beams ◽

10.1155/2021/6655499 ◽

2021 ◽

Vol 2021 ◽

pp. 1-10

Author(s):

Mikhail Veysman

Keyword(s):

Synchrotron Radiation ◽

Parametric Excitation ◽

Electron Bunch ◽

Short Pulse ◽

Spectral Parameters ◽

Electron Bunches ◽

Narrow Capillary ◽

Parametric Resonances ◽

Parametric Instabilities ◽

The One

It is shown that the dynamics of electrons accelerated in narrow capillary waveguides is significantly influenced by the parametric excitation of their betatron oscillations. On the one hand, this excitation can irreversibly spoil the emittance of an accelerated electron bunch that limits the possibilities of their practical use. On the other hand, controlled parametric excitation of betatron oscillations can be used to generate short-pulse sources of synchrotron radiation. The article analyzes the regions of parametric instabilities, their dependence on the parameters of accelerated electron bunches and guiding structures, and their influence on the dynamics of accelerated electrons. The parameters of the generated synchrotron radiation are also estimated. Measurements of the spectral parameters of synchrotron radiation can serve as a tool for diagnostics of betatron oscillations and their excitation in the case of parametric resonances.

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