| Paper | Title | Other Keywords | Page |
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| TUCA04 | Mechanism of Compression of Positron Clouds in the Surko Trap of the LEPTA Facility | positron, electron, accumulation, resonance | 20 |
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| Results from experimental studies of plasma storage in the Surko trap at the LEPTA facility are presented. The number of stored particles is found to increase substantially when using the socalled "rotating wall" method, in which a transverse rotating electric field generated by a cylindrical segmented electrode cut into four pairs is applied to the positrons storage region. The conditions of transverse compression of the plasma bunch under the action of the rotating field and buffer gas are studied. The optimal storage parameters are determined for these experimental conditions. Mechanisms of the action of the rotating field and buffer gas on the process of positron clouds storage are presented. | |||
| TUPSA16 | Electron Gun with Adiabatic Plasma Lens | electron, gun, cathode, focusing | 72 |
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Funding: This work supported by the Russian Foundation for Basic Research (grant № 12-02-00866-а) For researches on plasma physics has been designed and constructed the electronic gun with the cold cathode on energy about 250 keV. The electron beam have the parameters: time width of pulses 100 ns, current amplitude 100 A. The adiabatic plasma lens is used to reduce the beam size to the demanded value. The results of tests are presented. |
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| TUPSA25 | Acceleration of the Oppositely Charged Particles in the Single Stream | ion, electron, acceleration, heavy-ion | 88 |
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| One of the problems arising at extraction of heavy ions from plasma is removal of electrons from a stream of particles. Therefore possibility of simultaneous acceleration in one direction as ions (electric field), and electrons (pressure gradient) is represented rather interesting. In work when using the hydrodynamic description in the accelerating interval conditions of cold ions and hot electrons are studied. Possibility of excess by ions of speed of an ionic sound is shown, and the ratio of sizes of streams of be any. | |||
| WEPSB03 | System Power Microwave Impulse Compression Based on Double Forming Line | radiation, accumulation, operation, scattering | 159 |
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| Keywords: double forming line (DFL), compressor microwave pulses, microwave plasma discharger, resonator – storage, input power device (an input power), energy output device. The first part is devoted to the calculation and design compressor using a single-mode waveguides. We investigated the processes of accumulation and energy extraction from the resonator – storage of compressor, the dependence of the efficiency of energy extraction from the compressor on the plasma parameters of the discharge gap: n, q, m, v, r, h - the concentration, charge, mass, the frequency of collisions of free electrons, the radius and height of the cylinder through which flows the discharge. Refinement construction site energy output and its optimization, matching waveguide resonator - drive to the waveguide load in deriving energy from the compressor microwave was produced. The concept of a multi-compressor DFL was proposed and optimization under axial field was make to increase the dielectric strength and reduce the inductance of the discharge gap. In the second part of the paper questions, the design of the compressor DFL on oversized waveguides with working mode H01n was discusses. New constructions of power input devices was propose that allow not only to providing the necessary coupling coefficient with the feed path, but also greatly reduced the excitation of unacceptable modes in the resonator – storage. | |||
| WEPSB13 | Oversized Interference Switches of Active Microwave Pulse Compressors | cavity, extraction, coupling, operation | 183 |
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Funding: "Science" state order of the Russian Ministry of Education and Science. Results of simulation and experimental study of two types of the oversized interference switches are presented. The switch of the first type was developed on basis of the simulation of the oversized rectangular waveguide H-tee with the H01 operation mode. Conditions of effective operation of the first type switch as an energy extraction element of active microwave pulse compressors are determined. The output pulse power of 2.8 MW and pulse width of 3.5 ns with the corresponding amplification factor of 17.5 dB for were obtained in the X-band microwave pulse compressor prototype containing the storage cavity made of WR-284 waveguide and the switch made of the waveguide with the cross section area of 58×25 mm2. The results of experimental study of the oversized X-band interference switch of the second type with the synchronous energy extraction through a compact packet of common single mode switches incorporating the five identical waveguide tees are presented as well. Possibility of full synchronization of the switch packet is proved and the conditions of such synchronization are determined. Permissible quantity of the switches in a packet unit is estimated. The output pulse power of 0.8 MW, pulse width of 3.2 ns at the power gain of 12 dB and the pulse power of 2.2 MW, pulse width of 3.5 ns at the power gain of 16.5 dB were obtained when the energy extraction from the five different single mode resonant cavities and an oversized cavity respectively was synchronous. |
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| WEPSB38 | Multifunctional Extraction Channel Development Heavy Ion RFQ (Radio Frequency Quadrupole) | target, ion, simulation, rfq | 245 |
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| In the ITEP the Heavy Ion RFQ HIP-1 (Heavy Ion Prototype) provides ion beams for two different experimental programs. The first one is successfully ongoing and it is aimed to irradiation resistance investigation of reactor construction materials. Samples of new materials for reactors are irradiated by beams of iron, vanadium ions accelerated by the linac. The structure changes are investigated by both transmission electron microscope and atom-probe tomography. The second one is under development and it is aimed to investigate ion beam interaction with plasma and metal vapor targets. On the basis of beam dynamics simulation the design of new RFQ-output line for both experiments realization was developed. Details of beam dynamics simulation and output line design are presented and discussed in this paper. | |||
| THPSC48 | Hydrogen Nuclides Acceleration from Laser Plasma in the Diode with Magnetic Insulation of Electrons | laser, electron, ion, cathode | 435 |
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| New experimental results of obtaining accelerated deuterons in the small-sized diode with magnetic insulation are reported. The effective mode of ion acceleration to energies at 300 keV in the diode with a high voltage anode in order to initiate nuclear reactions D(d, n)3He is obtained with diode current ~0,5 kA and impulse duration ~1 mks in vacuum ~5*10-2 Pa. Containing deuterons laser plasma was generated at the anode during TiD target laser irradiation with a wavelength of 1.06 microns and a power density of ~5*1014 W/m2. Accelerating voltage impulse was formed using Arkadyev–Marx 20 cascade impulse voltage generator with air insulation. Diode cathode covers the anode symmetrically. It is a hollow cylinder permanent magnet with induction on the axis ~0,4 T. Magnetic insulation in accelerating gap leads to suppression of the accelerated electrons current at level of 0.5 in relation to the total diode current. Used methods of accelerating diode ion current, accelerating impulse voltage and penetrating radiations characteristics measurements are described. | |||
| THPSC49 | Hydrogen Nuclides Removing From Pulse Plasma Formations | cathode, vacuum, laser, ion | 438 |
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| The features of hydrogen nuclides extraction from vacuum-arc plasma and laser sources by electric field research results are presented in the report. Such sources can be used in accelerators injection systems and in neutron generators. These processes, found, are strongly influenced by electrostatic oscillations in the plasma boundary, which position continuously varies, in addition to the ions thermal motion. Such movement kinematics determined by the velocity field in plasma formation and its concentration reducing because of the ions extraction. On the basis of this model it shows that plasma boundary moves initially in the direction to the ejection electrode, then stops and begins quickly move back. An equation for the nuclides emission current density from hydrogen plasma surface for their quasiplanar extraction geometry is obtained. | |||
| THPSC50 | Neutron Accelerating Tubes with Microwave Deuterons Source Using Electron-cyclotron Resonance Effect | neutron, ion, cavity, ECR | 441 |
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| The physical principles of increased efficiency neutron accelerating tubes based on the microwave sources of heavy hydrogen nuclides, using the electron-cyclotron resonance effect (ECR) are considered. The authors' theoretical results are given on electromagnetic oscillations generation in the working volume of the ion source of the accelerating tube with the boundary excitation of a microwave discharge. Resonator and waveguide modes for ECR-plasma excitation are thus examined. Features of neutron generation in these accelerator neutron tubes based on microwave source of heavy hydrogen nuclides are analyzed. The algorithm is developed and numerical simulation of neutron pulse formation in neutron generators based on microwave source is done taking into account target shape and the possible deuterons resonant recharge. Frequency dependences of the energy flux density transmitted from an alternating electromagnetic field to the electron component of the plasma are obtained depending on the constant longitudinal magnetic field induction and pressure in the discharge chamber. The results of these studies could form the basis for the efficient domestic portable neutron generators development based on accelerating tubes with microwave hydrogen nuclides sources. | |||
| THPSC52 | Dynamics of Plasma-Beam Formations in the Acceleration Gap of the Pulse Neutron Generator-based Vacuum Neutron Tube | target, neutron, ion, vacuum | 447 |
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The analysis of dynamics of plasma flows containing deuterium, zirconium ions, and electrons in acceleration gap of the pulsed neutron generator vacuum neutron tube* is presented in the paper. The investigations have been undertaken with the use of code KARAT** for the two-dimensional time-dependant regime. The limiting currents of each component for the real geometry of acceleration gap have been determined. The differences between the values of these currents and those determined with the use of the Child-Langmuir equation have been demonstrated. The analysis of dynamics of plasma emitter in the gap has been performed by the example of accelerating voltage of 120 kV and pulse duration of 1.2 mks. It has been shown that the value of the current incoming in the gap from the ions source can differ strongly from the current value at the target. For increasing of this value the partitioning of acceleration gap with the use of conductive grid which is transparent for beam and has several geometric configurations has been proposed. The ring configuration of the emitter has been considered for the same purposes. The calculations have shown that the combination of these two methods described above can allow transporting deuterons current from the anode grid to the target without losses.
* E.P.Bogolubov, V.I.Ryzhkov, D.I.Yurkov. Conference "PNG and Technologies on Their Basis",2013,p.14. ** V.P.Tarakanov. User's Manual for Code KARAT. Berkeley Research Associates, Inc. 1992, p.127. |
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