RadiaBeam has developed a novel design of MW-class high-power RF windows to be used in high-power proton accelerators, such as SNS. This design is based on the utilization of a coaxial window between two waveguides to coaxial transitions, instead of a ceramic window in a uniform cylindrical waveguide, which provides several significant benefits. In this paper, we will present the RF and engineering design of this window.

Compact microwave electron linear accelerators must operate at high frequencies in order to maintain tight SWaP (size, weight, and power) requirements, set by modern applications. Currently, the frequencies are practically limited to X- and Ku-bands because of the availability of MW-class magnetrons, required to achieve beam energies of several MeV, and tight fabrication tolerances. The latter is associated with micron-level accuracy and further waveguide frequency tuning process, both increasing its costs dramatically. By implying a novel split structure fabrication approach, it is possible to relax these tolerances to the values of 10–20 μm and eliminate the tuning step, greatly reducing their total costs. This paper presents the results of microwave measurements of split X- and Ku-band accelerating structures of different types and discusses the benefits of our fabrication approach.

The replacement of radioactive sources with alternative technologies has been identified as a priority by international authorities, due to the risk of accidents and diversion by terrorists for use in Radiological Dispersal Devices. Many of these sources can be replaced with the X-rays produced by electron beams accelerated to MeV energies. However, the size, weight and costs of electron linacs must be significantly reduced to be considered for radioisotope replacement. RadiaBeam Technologies, LLC is developing a series of inexpensive compact electron accelerators in the 1-10 MeV range for radioisotope replacement such as Ir-192, Cs-137 and Co-60 for various applications. The dramatic level of miniaturization and cost-reduction was achieved thanks to the implementation of such innovative technologies as high-frequency magnetrons, split accelerating structure fabrication technology and solid-state Marx modulators. In this paper, we overview RadiaBeam's compact linac developments, discuss the enabling technologies, and report on the current progress.

В АО "Плутон" создана установка генераторного модуля СВЧ 2-см диапазона длин волн на основе технического решения – способа когерентного суммирования мощностей двух генераторов в волноводном сумматоре мощности – волноводном 3-дБ мосте. При этом на выходе модуля синхронизированного устройства мощность в пределах полосы синхронизации может достигать 95% от суммарной мощности генераторов.

In this work, we suggest and investigate new magnetless circulators based on three resonators connected in a loop and parametrically modulated in time with mutual phase lag. The first design consists of three Fano resonators with a spectrally asymmetric response, in contrast to schemes based on the Lorentz resonators explored thus far. The second design includes three Fano-Lorentz resonators, i.e., it also possesses spatial asymmetry. We demonstrate that the asymmetric approach provides strong and reversible isolation for the practically feasible modulation amplitude and rate. The results of our work are promising for precise measurements of superconducting radio frequency cavities with high Q-factor.

On the basis of previously carried out works [2, 3], it has been established that the most effective way for coherent summation of the power of two generators with a waveguide output is to use a waveguide 3-decibel bridge as an adder. In this case, the output power of the synchronized device within the synchronization band can reach 95% of the total power of the generators. Purpose of the work is to describe the installation «microwave module», which uses the method of coherent summation of the powers of two magnetrons in the power adder. Mutual phased synchronization of two magnetrons is provided by a phase shifter, matching is provided by a short-circuiting piston. The summed signal is sent to the output (antenna) path of the radar. The microwave generator module is designed to generate probing pulse signals in a multifunctional receiving-transmitting radar measuring complex. For the first time in Russia, JSC «Pluton» has created a «microwave module» installation in the 2-centimeter wavelength range, which makes it possible to use the principle of coherent addition of the powers of two commercially available magnetrons. The installation cost and manufacturing time are many times less than those for a newly developed magnetron with the parameters presented in this article.

Представлены результаты расчетных работ по исследованию процессов возбуждения колебаний в магнетроне с использованием компьютерного моделирования в 2- и 3-миллиметровом диапазоне длин волн, проводимых в АО «Плутон». Приведены экспериментальные данные линейки магнетронов, сконструированных на основании расчетных моделе

Abstract It is very important task to define the tolerances necessary for correct operation of an electron linac. The detuning of linac main parameters as frequency, RF field amplitude and phase can sufficiently influence to the beam parameters. It is highly important for linacs with high brightness beams which are necessary for light sources and colliders. It is also sufficient for industrial linacs. A linac section consists of regular and bunching parts. The influence of one cell detuning on electrodynamics parameters of the whole section was studied. Results of such simulation will discuss in this paper.

Work on the conceptual design of a dedicated fourth-generation fourth-generation Specialized Synchrotron Radiation Source (SSRS-4) is in progress at the Kurchatov Institute, Moscow. The project is being developed in collaboration with the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. In this paper, the initial results of our work on this project are reported, major directions of current research are presented, and possible areas of application of the SSRS-4 are outlined. The key element of the currently discussed design is a 6-GeV storage synchrotron with an orbit length of ~1300 m and the magnetic lattice that should provide a horizontal transverse emission of 70–100 pm rad. Further optimization may allow for reducing the emittance to 20–40 pm rad. Of the injection schemes under discussion, one features a full-scale booster synchrotron deployed in the same tunnel as the main storage ring, and the second is a topup linac. The latter can also be used as an electron-beam driver for a free-electron laser.

The project for a new injector linac for the Nuclotron–NICA accelerator tandem has been under development since 2015. The linac will accelerate protons and light ions to energies of 25 MeV and ∼7.5 MeV/nucleon, respectively. To fulfill the project, technology for fabricating superconducting RF cavities needs to be developed. The current status of the project, including the linac design, the required parameters of RF cavities, and our simulations of beam dynamics, is presented. Technological restrictions on the RF cavity parameters are discussed.