... Descriptors : (*ION BEAMS, SCATTERING), IONS, ARGON, ENERGY, DISTRIBUTION, PARTICLE ACCELERATOR TARGETS, COPPER, ...

Approved for public release, distribution unlimited. Reverse Ion Acceleration by Laser-Matter Interaction ... Backward Ion acceleration ? He++ Position ...

Structural failure of the accelerator grid in two-grid ion optics due to charge exchange ion erosion

The results of the pulse magnetic field formation of the accelerating magnetic system for the heavy ion collective accelerator prototype are presented. Magnetic field distribution in the acceleration region is measured. The relative gradient is close to t...

Determine the spatial distribution of flare-accelerated ions and electrons; Determine the angular distribution of relativistic electrons; Study the trapping ...

The purpose of this program is to evaluate the use of distributed charge exchange in a transmission-line type of inductive plasma accelerator. For this evaluation it is necessary to measure the flux and angular and energy distribution of the ions and neut...

made to characterize the spatial distribution of mass loss and the variation in erosion rates with ion dose to gain a better understanding of the local ...

The problem of the Coulomb explosion of a thin homogeneous foil with light and heavy ions is solved analytically in the context of laser ion acceleration. Spatiotemporal and spectral distributions of the accelerated light ions are obtained. The ions ...

The problem of the Coulomb explosion of a thin homogeneous foil with light and heavy ions is solved analytically in the context of laser ion acceleration. Spatiotemporal and spectral distributions of the accelerated light ions are obtained. The ions ...

beam to packets of sub-microsecond duration and accumulating beam current in the Proton Storage Ring, and distributing the ion beams to various targets, at which either...

Analytical and numerical calculations are presented for a reflexing electron beam type of collective ion accelerator. These results are then compared to those obtained through experiment. By constraining one free parameter to experimental conditions, the self-similar solution of the ion energy distribution agrees ...

Analytical and numerical calculations are presented for a reflexing electron beam type of collective ion accelerator. These results are then compared to those obtained through experiment. By constraining one free parameter to experimental conditions, the self-similar solution of the ion energy distribution agrees ...

Analytical and numerical calculations are presented for a reflexing electron beam type of collective ion accelerator. These results are then compared to those obtained through experiment. By constraining one free parameter to experimental conditions, the self-similar solution of the ion energy distribution agrees ...

... Descriptors : *Linear accelerators, *Ion accelerators, *Particle accelerator components, *Electron accelerators, *Proton accelerators, Electron beams ...

... (Author). Descriptors : *ION ACCELERATORS, ELECTROMAGNETS, ION BEAMS, FOCUSING, RINGS, USSR, LINEAR ACCELERATORS. ...

processes results in the final heliospheric distribution function of the heavy elements. The enhanced energetic heavy ion population may have a profound ...

... 4 more fast moving ions in the center of the acceleration channel than at the inner and outer regions. The relative width of the VDF axial main peak ...

Dynamics of particles in linear ion accelerator is investigated. Self-consistent distribution of phase density is obtained for intense ion beams in which longitudinal dimensions of buncher by far exceed the transverse ones. Inconsistency is considered of ...

The dynamics of the ions and neutral particles of a multicomponent plasma in an accelerator with closed electron drift orbits and an extended acceleration zone is analyzed in the kinetic approximation. Reactions induced by electron impact are taken into account. The electron temperature is calculated in the hydrodynamic approximation. ...

The charge-state distribution of 127I ions at the gas stripper of a tandem accelerator was measured for a wide range of charge states. When highly-ionized charge states were tuned, it was possible to identify spurious charge states originated in electron-loss collisions of the accelerated ions ...

Limits on beam current and emittance in proton and heavy ion linear accelerators resulting from space charge forces are calculated. The method involves determining equilibrium distributions in phase space using a continuous focusing, no acceleration, mode...

This review is devoted to processes in electron-ion beams and rings. The fundamentals of the distribution-function moments method in electron-ion beam physics and its applications to the dynamics of multicomponent beams with noncoincident dimensions are presented. Ion production and storage in electron-beam sources ...

Conductances of accelerator grids for hydrogen gas have been obtained by measuring the pressure distribution in high power ion source for Neutral Beam Injector. When the ion source is not operating, the conductances are in good agreement with calculated v...

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. Electron accumulation is impacted by the ion beam potential, ...

Linear accelerators driven by pulse forming networks and utilizing beam neutralization may be useful for obtaining high-current ion beams for inertial fusion applications. Such accelerators may be subject to longitudinal velocity bunching instabilities. These instabilities are studied with a computer simulation of longitudinal ...

The ion-hose (or fast-ion) instability sets limits on the allowable vacuum in a long-pulse, high current accelerator. Beam-induced ionization of the background gas leads to the formation of an ion channel which couples to the transverse motion of the beam. The instability is studied analytically and numerically for ...

Observations carried out with a laser-induced fluorescence diagnostic on several configurations of a multipolar discharge are presented. This diagnostic allows very accurate measurements of the ion velocity distribution function in the argon plasma and reveals the presence of double-hump velocity distribution functions due to ...

... warfare, joint planning, national and international ... a space charge wave accelerator. ... BEAMS, *ION ACCELERATORS, *PLASMA ACCELERATORS ...

In a quiescent plasma with a Maxwellian electron distribution, Bohm has shown that the pre-sheath accelerates ions to the speed (6 3 ) ...

Spacecraft observations at comet Halley as well as computer simulations have shown that pitch angle scattering of newborn cometary ions proceeds at a relatively fast rate, leading to relatively isotropic shell-like velocity distribution functions. Energization processes whereby shell distributions become more Maxwellian and a few ...

Controversy continues unabated concerning the detection of signatures of merging at low altitudes. One phenomenon required by nearly all models of merging is the acceleration of ions in the merging region by about the Alfven velocity. The authors report the observation of spatially discrete patches of precipitating accelerated ...

The Topaz3 auroral sounding rocket made the following observations concerning the transfer of precipitating auroral electron energy to transverse ion acceleration in the topside auroral zone. During the course of the flight, the precipitating electron beam was modified to varying degrees by interaction with VLF hiss, at times changing the beam into a ...

Electronegative plasmas are plasmas containing a significant fraction of negative ions, when magnetized they are very often segregated: the core is electropositive or weakly electronegative whereas a highly electronegative plasma forms at the periphery. At strong magnetic fields this segregation can lead to the formation of ion-ion plasmas almost free of ...

The current density distribution in an ion beam is close to the Gauss error curve. The ion beam pulsates with a frequency equal to the frequency of acceleration. A aitempt is made to explain the pre-axial density peak and pre- anxial luminescence. It is postulated that the diameter of the ...

Last results of the study of heavy ions acceleration by electrons trapped in moving 2-frequency 3-D RF wells are described. A linearized theoretical model of ions acceleration in a polarized spheroidal plasmoid is proposed. The equilibrium state of this plasmoid is described by the modified microcanonical ...

Magnetized test ions are subjected to acceleration through a numerically simulated oblique double layer in order to determine whether they emerge with velocity vectors aligned with or oblique to the ambient magnetic field. A criterion for oblique alignment, depending on the double-layer parameters and on the external magnetization, is obtained. When it is ...

The accelerator has been operating for six years, with a PIG ion source until December 1985 and with an ECR ion source since this date. Main statistical results about the running time distribution are given. Technical improvements, machine studies and bea...

On the basis of the distribution function momentum method equations are derived, describing the change in time of coordinates of mass local centers and of root-mean-square dimensions of an accelerated electron-ion ring. The adiabatic invariants generalizi...

The physics of deep inelastic heavy ion collisions is briefly reviewed in the light of the experimental capabilities offered by large Tandem Accelerators. Three aspects are selected for illustration. The first is the problem posed by the angular distribut...

An ion bean buncher was developed at ANL for bunching all ion species through a tandem accelerator. Transit time variations through the tandem, caused by ripple and fluctuations in the injection and lens power supplies and terminal voltage, and to varying voltage distributions in the ...

Recent Oak Ridge work is summarized on projectile energy gain by image charge acceleration, scattered ion charge distributions, and K-Auger electron emission during low energy grazing interactions of highly charged Pb, I, O, and Ar ions with a Au(110) sur...

Recent Oak Ridge work is summarized on projectile energy gain by image charge acceleration, scattered ion charge distributions, and K-Auger electron emission during low energy grazing interactions of highly charged Pb, I, O, and Ar ions with a Au(110) surface.

The selfconsistent theory of ion diffusive shock acceleration and the associated generation of Alfv�n waves are presented. The wave intensity satisfies a wave kinetic equation and the ion distribution function satisfies the diffusive transport equation. These quasilinear non-stationary equations are solved ...

Laser ion sources (LIS) are employed with success to generate, in vacuum, Ge and Ti ion beams with high current, ion energy, charge states and directivity. Nanoseconds infrared laser pulses, with intensities of the order of 1010 W/cm2, induce high ablation in Ge and Ti targets. Ions are produced in vacuum with ...

Equations are derived for the change of the second-order moments of the distribution functions of the ions in a ring. The storage of singly-charged ions of a neutral gas and the successive increase in the charge state of the ions are investigated. From the equations for the moments we obtain a system of equations ...

Copper plasma with hyperthermal directed velocity (8.8 eV) but very low temperature (0.6 eV) has been obtained using self-sputtering far above the runaway threshold. Ion energy distribution functions (IEDFs) were simultaneously measured at 34 locations. The IEDFs show the tail of the Thompson distribution near the magnetron target. ...

The one-dimensional expansion of a plasma slab is studied using a kinetic description of the electrons based on an adiabatic invariant. The distribution function of the electrons is determined at any time and any position. Solution of the Poisson equation then enables us to determine the electric potential and the ion acceleration. ...

... Accelerator. A New Experiment in the Physics of Elementary Particles,. Corporate ... Subject Categories : PARTICLE ACCELERATORS. ...

... Descriptors : *ION ACCELERATORS, *LINEAR ACCELERATORS, SYMPOSIA, SEMICONDUCTOR DEVICES, PULSE GENERATORS, SOLID ...

... Descriptors : *PARTICLE ACCELERATORS, CYCLOTRONS, IONS, LINEAR ACCELERATORS, MAGNETIC PROPERTIES, MATRICES ...

Coulomb explosion of a charged, nonuniform, and spherically symmetric cluster with a finite ion temperature is investigated. The spatial distributions of the density and mean velocity of accelerated ions, as well as their energy spectra, are obtained and analyzed as functions of the initial temperature. It is shown ...

We study fluctuations driven by the parametric instabilities of an Alfven-cyclotron pump wave, which have an influence on the shape of the ion velocity distributions in the solar wind. Longi-tudinal ion-acoustic waves (IAW) and transverse ion-cyclotron (ICW) daughter waves, resulting from the parametric decay, can ...

A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the ...

... ACCELERATORS, *ION ACCELERATORS, RINGS, VACUUM APPARATUS, ELECTRONS, MAGNETIC FIELDS, CROSSED FIELD DEVICES ...

... warfare, joint planning, national and international ... tube ion accelerator as neutron ... TUBES, ION ACCELERATORS, MAINTENANCE EQUIPMENT ...

Three-grid ion accelerator in which accelerator grid is biased at negative potential and decelerator

... Descriptors : *ION ACCELERATORS, *LINEAR ACCELERATORS, ELECTRIC FIELDS, CATHODES, ELECTRON BEAMS, INSTABILITY, SPACE ...

We apply test-particle numerical simulations to model the acceleration of inner-source C+ by a strong interplanetary shock. The model consists of three distinct parts: (a) the distribution of inner-source pickup ions; (b) the initial acceleration of pickup ions (to produce seed particles) for a ...

Equilibrium charge state distributions have been measured in many laboratories for both solids and gases with ions of a very large number of elements, and the range of ion velocities has been extended as new accelerators have become available. Many different charge changing cross sections contribute to any ...

A method based on the moments of the distribution function is used to derive equations giving the time evolution of the coordinates of the local centers of mass and the mean square dimensions of an accelerated electron--ion ring. Adiabatic invariants are found which generalize the ordinary betatron-oscillation invariants to the case of ...

High energy beams of high ion currents from a Tandem accelerator are a common requirement in nuclear physics, materials science and Accelerator Mass Spectrometry (AMS) research. In many cases, molecular beams are chosen from the ion source to achieve a high ion source yield for the negative ...

... The Distribution of Ions and Electrons in the Earth's Exosphere ... THE DISTRIBUTION OF IONS AND ELECTRONS IN THE EARTH'S EXOSPHERE ...

... SCATTERING, *PARTICLE COLLISIONS, *ION ACCELERATORS, *ION ION INTERACTIONS, VELOCITY, ION DENSITY, LOSSES, NUCLEAR ...

... SEE), Latchup, Cyclotron, Accelerator, Lawrence ... ION ACCELERATORS, *CYCLOTRONS, TEST AND EVALUATION, FREQUENCY, IONS ...

... possibility that at high current densities an ... ACCELERATORS), SPACE CHARGE, MAGNETIC FIELDS ... EMISSION, TUNGSTEN, IONS, ION BEAMS ...