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The electrostatic corrector is a component of the mass separator of the Gas cell Laser ionization and Separation (GALS) facility and is used to correct the beam of single-charged ions emerging from the analyzing magnet. The results of the development of the corrector and its calculation are presented in this work.

Two main cyclotron beam extraction methods using a stripping foil and an electrostatic deflector are considered. Computation results are presented for two cyclotrons, TR-24, IPHC, Strasbourg, France (stripping foil extraction), and DC-140, FLNR, JINR, Dubna, Russia (electrostatic deflector extraction).

The creation of a new multipurpose isochronous cyclotron DC140 is being carried out at the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research. The DC140 cyclotron is intended for microchip testing on radiation resistance, the production of track pore membranes, and applied physics. The cyclotron will accelerate heavy ions with mass-to-charge ratio A/Z ranging from 5 to 8 up to fixed energies of 2.1 and 4.8 MeV per nucleon. The new cyclotron DC140 will be created as a deep reconstruction of the DC72 cyclotron. In particular, it is supposed to adapt the DC72 electromagnet for obtaining new acceleration regimes. In this paper, the main parameters of the DC72 and DC140 magnetic systems, the results of calculations and measurements of the magnetic field, and estimations of the possibility of formation of new acceleration regimes with minimal changes in the DC72 magnetic system are presented.

The basic facility of the Factory of Superheavy Elements (SHE), the DC-280 cyclotron, in the Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research has been completed. Both new and experimentally tested engineering solutions of the laboratory underlie the project. Planned beam intensities of up to 10 pμA of ions with average masses (A ~ 50) are one order of magnitude higher than those produced at the U-400 cyclotron up to now. From 2016 to 2018, the DC-280 cyclotron equipment was installation and set up. The first 84Kr14+ ion beam was accelerated in the DC-280 on December 26, 2018, and extracted to the accelerated ion transportation channel on January 17, 2019. In March 2019, beams of accelerated 84Kr+14 ions with an intensity of 1.36 pμA and 12С+2 ions with an intensity of 10 pμA were extracted from the DC-280 to the beam transportation channel with an energy of about 5.8 MeV/nucleon. The main task of the new accelerator is to implement a long-term research program at the SHE Factory aimed at the synthesis of new elements (Z ≥ 119) and a detailed study of nuclear–physical and chemical properties of previously discovered elements nos. 112–118.

The status of the project of the DC-280 cyclotron is presented. The DC-280 will be the basic facility of the Super Heavy Element Factory which is being created at the FLNR JINR. The energy of the ions extracted from the cyclotron will be vary from 4 up to 8 MeV/amu. The expected ion beam intensity at DC-280 extraction is 10 pμA for ions with masses of 50–60. The main parts of the DC-280 are already made and are being assembled. In according to FLNR plans the cyclotron has to be assembled in the period from 2016 to 2017. The cyclotron commissioning will be in 2018.

For a rotating ring-shaped target irradiated by a heavy-ion beam, a differential equation for computing the stationary distribution of the temperature averaged over the cross section is derived. The ion-beam diameter is assumed to be equal to the ring width. Solving this equation allows one to obtain the stationary temperature distribution along the ring-shaped target depending on the ion-beam, target, and cooling-gas parameters. Predictions are obtained for the rotating target to be installed at the DC-280 cyclotron. For an existing rotating target irradiated by an ion beam, our predictions are compared with the measured temperature distribution.

A way to obtain a uniform distribution of a heavy-ion beam on a moving target by scanning the beam over the target surface is considered. The scanning is performed by the horizontal and vertical scanner. A method is proposed for calculating the particle density distribution on the target with allowance for the influence of the horizontal slit in front of the target. Since the scanner forces deflecting the center of mass of the beam are periodic, the ion density distribution on the target is also a periodic function in the target motion direction and the spatial period of the function depends on the ratio of the scanner frequencies. With the high-frequency vertical scanner, a rather uniform particle density is obtained on the target despite considerable ion density inhomogeneities in the beam. With the slit, the particle density inhomogeneity on the target sharply increases when the scanned beam goes beyond the slit height.

Equations for calculating the microbeam formation channel are derived. The channel consists of two coaxial diaphragms with radii r 1,2 and a target with a radius r T . With the given ion beam parameters, distance between the diaphragms L, beam radius on the target r T , and desired efficiency of beam passage through the diaphragms η0, the system of equations allows calculating the distance from the second diaphragm to the target L 1 and the radii of both diaphragms. Dependences of the diaphragm radii and the distance L 1on the efficiency η0 at a fixed target radius r T and of the efficiency η0 and the diaphragm radii r 1,2 on the distance L at a fixed distance L 1 are found. The effect of the deviations of the main channel and beam parameters from the optimum values on the microbeam formation efficiency is estimated. Tolerable values are determined for the diaphragm displacement and background magnetic field.

The equations and algorithms for calculating the charged-particle-beam dynamics in bending magnets and electrostatic deflectors, which are used in the ion-beam transport lines and spectrometers, are presented. Calculations of the electromagnetic field 3D maps are illustrated. The value of the electromagnetic-field nonlinearities and their effect on the particle dynamics are analyzed. The simulation of the ion dynamics in the axial injection beam line of the DC-280 cyclotron and GALS spectrometer created at the JINR Laboratory of Nuclear Reactions (FLNR) is described.

A new scanning system is considered. The system is developed at JINR and has a number of characteristic features. The windings of the bending magnets with a large number of ampere-turns operate at relatively low frequencies (≤20 Hz) to maintain the reactive power within reasonable limits. The winding power supplies use feedback systems to shape currents of the given waveform and amplitude. The main structural features and parameters of the prototype magnet and the results of developing and testing the electronic circuit for supplying the magnet with a current of the given waveform are presented. Density distributions of various ions on the target are calculated for one of the U400-M cyclotron beam lines using the parameters of the new scanners.

The design of the high-voltage axial injection system for the DC-280 cyclotron that is being constructed at the Flerov Laboratory of Nuclear Reactions (FLNR) at the Joint Institute for Nuclear Research (JINR) is presented. The injection system will make it possible to efficiently inject ions of elements ranging from helium to uranium with the ratios of their atomic mass to the charge varying from 4 to 7.5.

The optimization of the field distribution of the analyzing magnet installed in the axial injection beam line of the cyclotron DC-280 is carried out. This optimization is done on the basis of a three-dimensional calculation of the magnet field. The optimum value of the basic geometrical characteristics of the magnet influencing the form of the field distribution is found.

The specialized DC-110 heavy ion cyclotron has been developed and created at the Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research for the BETA research and production complex in Dubna (Russia), which allows producing intense accelerated Ar, Kr, and Xe ion beams with a fixed energy of 2.5 MeV/nucleon. Commissioning works on the cyclotron complex, during which the design parameters were obtained, were carried out at the end of 2012. During commissioning of the accelerator, vertical displacement of the beam was found at the final acceleration radii and during its extraction. It is shown that the main cause of this displacement was the occurrence of a radial component of the magnetic field in the median plane of the magnet caused by asymmetry of the magnetic circuit. Vertical beam displacement was corrected by creating asymmetry of the current in the main electromagnet winding of the DC-110 cyclotron.

The DC-110 heavy ion cyclotron for industrial production of track membranes has been developed and created at the Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research. The cyclotron is equipped with an electron cyclotron resonance ion source operating at a frequency of 18 GHz. The accelerator complex was put into operation in 2012 and 40Ar6+, 86Kr13+, and 132Xe20+ ion beams with a energy of 2.5 MeV/nucleon and intensity of 13, 14.5, and 10.5 μA, respectively, were produced. Irradiation of a polymer film was carried out on a specialized channel and track membranes with a high uniformity of pores were obtained. The DC-110 accelerator complex can produce up to 2 million square meters of track membranes per year.

Diaphragms or slits (to limit the size of the ion beam) and degraders (to reduce the kinetic energy of ions) are often used in beam lines for ion transport. When an ion beam travels through these elements, parameters such as rms sizes, angle, and momentum spread change abruptly. This fact should be taken into account in calculating the subsequent sections of the beam line. Formulas are derived for determining new parameters of the ion beam immediately after its passage through those elements. The results of calculations are given regarding the transport of different kinds of heavy ions in the beam lines of the U400M cyclotron of the Joint Institute for Nuclear Research (JINR) Flerov Laboratory of Nuclear Reactions intended for testing electronic microchips.

The flat-top cavity of the radio-frequency accelerating system designed at the Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, for the DC-280 cyclotron is described. The cyclotron is intended for increasing the capabilities and efficiency of experiments on the synthesis of super-heavy elements and an investigation of their nuclear physical and chemical properties. The DC-280 isochronous heavy-ion cyclotron will produce accelerated beam of ions in the range from neon to uranium. The parameters, design, and results of the experimental and 3D computer modeling of the flat-top cavity of the RF accelerating system of the DC-280 cyclotron are reported.

To increase the intensity of an ion beam injected in a cyclotron, the possibility of focusing by an axial potential electrode is investigated. The influence of the electric field of an electrode on the beam emittance and that of particle losses on an electrode are estimated. The results of our numerical simulation are compared with theoretical estimations.

The DC-350 accelerator complex is described and its technical characteristics are presented.

The possibility of recovering the particle distribution function at any point of the four-dimensional transverse phase volume “x, x′, y, y′” using the results of measurements with the pepper-pot method is demonstrated. The proposed method for processing experimental data is based on the assumption that the one-to-one correspondence between holes in the mask and their images on the screen is established. Such a preliminary calibration should be experimentally performed on the measured ion beam. The method of moments is used for the recovery of the distribution function. Using Legendre polynomials for processing experimental results reduces the problem to a sequence of recurrence relations. A numerical simulation of the measurement process demonstrated that the recovery accuracy of the particle distribution function is about ±10%.

An electrostatic storage ring for low-energy ions with a design energy of 50 keV is presently being set up at the Institut fur Kernphysik der Johann Wolfgang Goethe-Universitat Frankfurt am Main, Germany (IKF). This new device will provide a basis for new experiments on the dynamics of ionic and molecular collisions, as well as for high precision and time resolved laser spectroscopy. In this article, the design parameters of this instrument are reported.

Industrial production of nuclear filters has been implemented at the IC-100 cyclotron complex of the Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research. After the complete upgrade, the cyclotron was equipped with the superconducting ECR ion source and the system of external axial beam injection. The implantation complex was equipped with the special transportation channel with the beam scanning system and the setup for irradiation of polymer films. Intense beams of heavy ions Ne, Ar, Fe, Kr, Xe, I, and W with an energy of ∼1 MeV/nucleon were obtained. the properties of irradiated crystals were studied, different polymer films were irradiated, and several thousands of square meters of track membranes with pore densities varying in a wide range were produced. Other scientific and applied problems can be solved at the cyclotron complex.

An accelerator complex has been developed on the basis of the DTs-60 cyclotron for performing scientific and applied research and for commercial application in nanotechnology. The complex was designed and constructed at the Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research for the Interdisciplinary Scientific and Research Center at the L. N. Gumelev Eurasian National University (Kazakhstan). Intense beams of heavy ions of Ne, Ar, Kr, and other elements have been obtained and accelerated in the cyclotron. Various polymer films have been irradiated and several control batches of track membranes have been prepared in a wide range of densities of the openings. The complex is a unifying factor in the development of technologies, science, and science-intensive business and is intended for producing track filters, developing commercial technologies using nano-and microstructures based on nuclear membranes and for creating a scientific environment in Kazakhstan.

GALS is the experimental setup intended for production and research of isobaric and isotopically pure heavy neutron-rich nuclei. The beam line consists of two parts. The initial part is used for transport of the primary 136Xe ion beam with the energy of 4.5-9.0 MeV/amu from the FLNR cyclotron U-400M to the Pb target for production of the studying ion beams. These beams have the following design parameters: the charge Z = +1, the mass A = 180-270 and the kinetic energy W = 40 keV. The second part placed after the target consists of the SPIG (QPIG) system, the accelerating gap, the electrostatic Einzel lens, 90-degree spectrometric magnet (calculated value of the mass-resolution is equal to 1400) and the beam line for the transportation of the ions from the magnet focal plane to a particle detector. The results of simulation of the particle dynamics and the basic parameters of all elements of the beam line are presented.

A cyclotron complex has been developed at the Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, for a wide spectrum of applied studies in the field of nanotechnologies (template technologies, track membranes, surface modification, etc.). This complex includes a specialized DC-110 cyclotron, which gives high intensity beams of accelerated Ar, Kr, and Xe ions with a fixed energy of 2.5 MeV/nucleon. This cyclotron is equipped by an external injection system with an ECR ion source operating at a frequency of 18 GHz. The cyclotron electromagnet with a pole diameter of 2 m offers a working magnetic field on a level of 1.67 T. The fixed RF frequency is 15.5 MHz. The beam is extracted from the cyclotron by the electrostatic deflector. The main parameters of DC-110 cyclotron are presented in this paper.

The review on a source of synchrotron hard X-ray and coherent infrared radiation at JINR is presented. The requirements on the SR source and on the accelerating complex are given. The structure scheme of the SRS is described. The preliminary calculations of the QBA lattice of the main ring are performed.

The DC-350 is an isochronous cyclotron designed in the Flerov Laboratory of Nuclear Reaction (FLNR). It is intended for accelerating ions with a mass-to-charge ratio A/Z within an interval of 5–10 and with an energy of 3–12 MeV/u at the extraction radius. These ion beams will be used in nuclear and applied physics experiments. The paper describes the results of a 3D magnet simulation. The cyclotron magnet and IM90 analiziting-bend magnet of the axial injection channel are studied here. The influence of correction coils on the cyclotron magnet is calculated. All magnet fields were calculated by MERMAID 3D code [1].

Ion source extraction potentials are often in the range of 10 - 30 kV where space-charge forces are detrimental to beam quality. Use of higher extraction voltage results in reduced space-charge effects but may be too high for subsequent injection. A scheme of beam extraction at 50 kV followed by deceleration to 25 kV is considered. Simulation results with an argon beam in such a beam line are presented.

This paper presents the results of a numerical simulation of the process of formation of a nonstationary well in the gap between the front of the cathode flare and the anode taking into account the floating potential at the boundary of the expanding plasma. It has been shown that in a vacuum diode a potential well can form whose lifetime lies on the nanosecond scale. Based on the results obtained, an explanation is given to the effect of collective acceleration of ions in a vacuum spark discharge.

A status report of the design and fabrication of a new, fully superconducting electron cyclotron resonance ion source will be presented. The Superconducting Source for Ions (SuSI) first will operate at 18+14.5GHz microwave frequencies. A short description of the magnet structure and the injection and extraction hardware will be presented. Several innovative solutions are described, which will allow maximum flexibility in tuning SuSI in order to match the acceptance of the coupled cyclotrons. Details of an ultrahigh temperature inductive oven construction are given as well as a description of the low-energy beam transport line.

The formation of a deep nonstationary potential well in the gap between the cathode flare front and the anode has been modeled with allowance for a floating potential at the boundary of an expanding plasma. It is shown that a long-lived potential well with a lifetime on the order of nanoseconds can form in the vacuum diode. The obtained results provide an explanation of the phenomenon of collective ion acceleration at the spark stage of vacuum discharge.