Suchergebnisse

To create a compact system for scanning the beam along the conveyor, this paper considers the horizontal
placement of the accelerator with a magnetic system with rotating the beam by 90◦
. A three-dimensional
simulation of the magnetic system and the dynamics of electrons in it was performed. Dose distributions
were also obtained in the near-surface region of the irradiated object, on the basis of which the optimal laws
of change in the current and voltage of the scanning magnet were determined, which provide the required
conditions for irradiating the product

One of the key problems of contemporary accelerator physics has been an increase of the rate of the energy
gain in linear electron accelerators. The physical limits of the accelerating field intensity for the normal and
superconducting accelerating structures have been practically reached; therefore, new acceleration schemes are
being considered, primarily acceleration in plasma and wakefield acceleration. It is suggested to consider an
opportunity using of a bunch generated in a laser-plasma channel for injection into a traditional metal structure.
It has been shown that an electron source based on a cluster plasma can generate a short (from 0.1 to 1.0 ps)
electron bunch with an energy of several hundred keV, which makes it possible to consider such a source as
an alternative to a photocathode. Next, the beam must be captured in the acceleration mode and accelerated up
to an energy of 50 MeV with the possibility of energy tuning. The features of such accelerator, the features
of the electron bunch capturing in the acceleration mode, and the possible values of the energy spectrum
in such a system will considered. The features of such a source, including the possible energy spectrum, the features of the electron bunch capturing with an extremely wide spectrum in the acceleration mode,
as well as the electrodynamic characteristics of the accelerating structures are considered in the paper. The
beam dynamics simulation was carried out using the BEAMDULAC package developed at the Department
of Electrophysical Facilities of the National Research Nuclear University MEPhI. The main results of the
optimization of electrodynamic characteristics of the accelerating structures was also reported.

Considers authorization of funds for an AEC linear electron accelerator to be located at Stanford Univ. Appendixes include. a. "Proposal for a Two-Mile Linear Electron Accelerator," by Stanford Univ, Apr. 1957 (p. 283-426). b. "Review of the Stanford Proposal for a Two-Mile Linear Electron Accelerator," by William M. Brobeck P Assocs, June 1958 (p. 427-525). c. "Site Feasibility of Stanford's Proposed Two-Mile Linear Electron Accelerator," by Frank W. Atchley and Robert O. Dobbs, July 1959 (p. 577-649). ; Record is based on bibliographic data in CIS US Congressional Committee Hearings Index. Reuse except for individual research requires license from Congressional Information Service, Inc. ; Indexed in CIS US Congressional Committee Hearings Index Part VII ; Considers authorization of funds for an AEC linear electron accelerator to be located at Stanford Univ. Appendixes include. a. "Proposal for a Two-Mile Linear Electron Accelerator," by Stanford Univ, Apr. 1957 (p. 283-426). b. "Review of the Stanford Proposal for a Two-Mile Linear Electron Accelerator," by William M. Brobeck P Assocs, June 1958 (p. 427-525). c. "Site Feasibility of Stanford's Proposed Two-Mile Linear Electron Accelerator," by Frank W. Atchley and Robert O. Dobbs, July 1959 (p. 577-649). ; Mode of access: Internet.

The possibilities are analyzed for studying the yields of reactions 13C(𝛾, 𝑝) 12B, 14N(𝛾, 2𝑝) 12B, 14N(𝛾, 2𝑛) 12N by measuring the induced (12B, 12N)-activity with telescopes of thin Δ𝐸–detector in time intervals between electron accelerator pulses. For production of (12B, 12N)- nuclei and registration of their decay, estimates are given taking into account the parameters of the electron beam, Ta–radiator and irradiated targets made from graphite or NH4NO3, as well as the parameters of scintillation Δ𝐸 detector telescopes made from thin plastic plates.

The development of accelerator technology in Poland is strictly combined with the cooperation with specialist accelerator centers of global character, where the relevant knowledge is generated, allowing to build big and modern machines. These are relatively costly undertakings of interdisciplinary character. Most of them are financed from the local resources. Only the biggest machines are financed commonly by many nations like: LHC in CERN, ILC in Fermi Lab, E-XFEL in DESY. A similar financing solution has to be implemented in Poland, where a scientific and political campaign is underway on behalf of building two big machines, a Polish Synchrotron in Kraków and a Polish FEL in Świerk. Around these two projects, there are realized a dozen or so smaller ones.

1 Historical Survey -- 2 Basic Principles of Electron Optics -- 2.1. Rotationally Symmetric Lenses in the Bell-Shaped Field Approximation -- 2.2. Rotationally Symmetric Lenses with Arbitrary Field Distribution -- 2.3. Aberrations Resulting from Misalignment -- 2.4. Multipole Fields for Beam Correction -- 2.5. Image Contrast -- 2.6. Further Sources of Error -- 2.7. Fixed Beam and Scanning Mode -- 3 Superconducting Devices in Electron Microscopy -- 3.1. Advantages of Superconducting Devices -- 3.2. Technical Problems -- 4 Lens Design and Testing -- 4.1. Lens Design and Field Distribution -- 4.2. Correction Systems for Superconducting Objective Lenses -- 4.3. Testing of Objective Lenses -- 5 Systems with Superconducting Lenses -- 5.1. Tested Systems -- 5.2. Projected Systems -- 6 Other Superconducting Elements for Electron Microscopy -- 6.1. Superconducting High-Voltage Beam Generator -- 6.2. Magnetic Dipoles -- 7 Proposed Superconducting 3-MV Microscope -- 7.1. Accelerator -- 7.2. Spectrometer -- 7.3. Microscope Column -- 7.4. Further Improvements of the System -- Appendixes -- A. Superconducting Electron Optical Systems for High-Energy Physics -- A.1. General Remarks -- A.2. Magnet Designs -- B. Application of Electron Microscopy to Basic Research on Superconductivity -- B.1. Imaging by the Decoration Method -- B.2. Imaging by Electron Shadow Microscopy -- B.3. Imaging by an Electron Mirror Microscope -- B.4. Imaging by Lorentz Microscopy -- B.5. Imaging by a Vortex Electron Microscope -- References.

Laser-wakefield accelerators (LWFAs) were proposed more than three decades ago, and while they promise to deliver compact, high energy particle accelerators, they will also provide the scientific community with novel light sources. In a LWFA, where an intense laser pulse focused onto a plasma forms an electromagnetic wave in its wake, electrons can be trapped and are now routinely accelerated to GeV energies. From terahertz radiation to gamma-rays, this article reviews light sources from relativistic electrons produced by LWFAs, and discusses their potential applications. Betatron motion, Compton scattering and undulators respectively produce x-rays or gamma-rays by oscillating relativistic electrons in the wakefield behind the laser pulse, a counter-propagating laser field, or a magnetic undulator. Other LWFA-based light sources include bremsstrahlung and terahertz radiation. We first evaluate the performance of each of these light sources, and compare them with more conventional approaches, including radio frequency accelerators or other laser-driven sources. We have then identified applications, which we discuss in details, in a broad range of fields: medical and biological applications, military, defense and industrial applications, and condensed matter and high energy density science.

At present, a fourth-generation synchrotron radiation source USSR (Synchrotron & Laser), which will the one of
the world's largest scientific centers is being designed in Russia. Its creation will make it possible to carry out
experiments to study the structures of a wide range of objects in various disciplines at a qualitatively new level
compared to the previous generation of sources. The overall facility layout includes a 6 GeV main storage ring
and a linear electron accelerator (linac) at full energy. It is proposed to use one linear accelerator with two RF
guns. A RF gun with a photocathode can be used to generate a bunch train for a Free Electron Laser (FEL), a
RF gun with a thermionic cathode can be used for injection into a storage ring. Both injectors will operate with
the same regular part of the linear accelerator, consisting of 100-120 identical sections. The purposed transverse
emittance in the main storage ring will be 50–100 pm.rad. The development of a general linear accelerator
scheme in order to minimize the beam energy spread and the output transverse emittance, the optimization of
the geometric and electrodynamics parameters of the accelerating structures, and the beam dynamics analysis in
this linear accelerator will be discussed in the article. The beam dynamics simulation was performed using the
BEAMDULAC code developed at the Department of Electrophysical Facilities of the National Research Nuclear
University MEPhI.

http://accelconf.web.cern.ch/AccelConf/IPAC2011/papers/thpz003.pdf ; International audience ; The SuperB collider project [1] has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (1036 cm-2 s-1) asymmetric e+e- collider at the (4S) energy. The design is based on a "large Piwinski angle and Crab Waist" scheme already successfully tested at the DANE -Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, such as two beams (e+ at 6.7, HER, and e- at 4.2 GeV, LER) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the /charm energy threshold with a luminosity of 1035 cm-2 s-1. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation (SR) users is the latest feature included in the design [2]. The lattice has been recently modified to accommodate insertion devices for X-rays production.

http://accelconf.web.cern.ch/AccelConf/IPAC2011/papers/thpz003.pdf ; International audience ; The SuperB collider project [1] has been recently approved by the Italian Government as part of the National Research Plan. SuperB is a high luminosity (1036 cm-2 s-1) asymmetric e+e- collider at the (4S) energy. The design is based on a "large Piwinski angle and Crab Waist" scheme already successfully tested at the DANE -Factory in Frascati, Italy. The project combines the challenges of high luminosity colliders and state-of-the-art synchrotron light sources, such as two beams (e+ at 6.7, HER, and e- at 4.2 GeV, LER) with extremely low emittances and small beam sizes at the Interaction Point. As unique features, the electron beam will be longitudinally polarized at the IP and the rings will be able to ramp down to collide at the /charm energy threshold with a luminosity of 1035 cm-2 s-1. The relatively low beam currents (about 2 A) will allow for low running (power) costs compared to similar machines. The insertion of beam lines for synchrotron radiation (SR) users is the latest feature included in the design [2]. The lattice has been recently modified to accommodate insertion devices for X-rays production.

CompactLight is a consortium funded by the European Union through the Horizon 2020 Research and Innovation Programme under Grant Agreement No. 777431. This report summarizes science requirements and performance specification for the CompactLight x-ray free-electron laser.

The views expressed in this thesis are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government. ; Today's surface ships are faced with an increased vulnerability to anti-ship cruise missiles, due to a change from operating in open oceans to primarily operating in the world's littorals. One possible solution to counter this threat is the use of a high-energy laser to destroy the missiles in flight. The Free Electron Laser is possibly the best choice of lasers for a marine environment since its wavelength can be changed over a wide range allowing the operator to choose the best wavelength to transmit through the atmosphere. Material damage studies on various anti-ship cruise missile materials were carried out at Thomas Jefferson National Accelerator Facility (TJNAF) in Newport News, Virginia. Experimental procedures presented in this report allow a scaled down laser of a few hundred to a few thousand watts to evaluate the damage from a weapon size laser of the megawatt class. The EEL beam bombards the target with a steady stream of picosecond length pulses at rates of 18MHz or greater. No other experiments have previously been done to explore the effects of the EEL pulse on materials. This report contains the work of several theses conducted at the Naval Postgraduate School over the past two years, and has been a productive cooperation among NPS, TJNAF, NRL, and NSWD at Port Hueneme, to the benefit of the Department of Defense. ; Prepared for: Naval Postgraduate School Monterey, CA 93943-5000 ; N0001401WR30407. ; Approved for public release; distribution is unlimited.

This report presents the conceptual design of a new European research infrastructure EuPRAXIA. The concept has been established over the last four years in a unique collaboration of 41 laboratories within a Horizon 2020 design study funded by the European Union. EuPRAXIA is the first European project that develops a dedicated particle accelerator research infrastructure based on novel plasma acceleration concepts and laser technology. It focuses on the development of electron accelerators and underlying technologies, their user communities, and the exploitation of existing accelerator infrastructures in Europe. EuPRAXIA has involved, amongst others, the international laser community and industry to build links and bridges with accelerator science — through realising synergies, identifying disruptive ideas, innovating, and fostering knowledge exchange. The Eu-PRAXIA project aims at the construction of an innovative electron accelerator using laser- and electron-beam-driven plasma wakefield acceleration that offers a significant reduction in size and possible savings in cost over current state-of-the-art radiofrequency-based accelerators. The foreseen electron energy range of one to five gigaelectronvolts (GeV) and its performance goals will enable versatile applications in various domains, e.g. as a compact free-electron laser (FEL), compact sources for medical imaging and positron generation, table-top test beams for particle detectors, as well as deeply penetrating X-ray and gamma-ray sources for material testing. EuPRAXIA is designed to be the required stepping stone to possible future plasma-based facilities, such as linear colliders at the high-energy physics (HEP) energy frontier. Consistent with a high-confidence approach, the project includes measures to retire risk by establishing scaled technology demonstrators. This report includes preliminary models for project implementation, cost and schedule that would allow operation of the full Eu-PRAXIA facility within 8—10 years.