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The dynamics of charged particles in the Penning–Malmberg–Surco trap with a rotating electric field [1–3] (the Charlton trap) is investigated. Two different algorithms for determining Lyapunov characteristic exponents for solutions of a nonstationary system describing the dynamics of particles in a trap are constructed and realized. This allows us to construct approximate analytical solutions and analyze the behavior of the envelope of the particle beam, and not only of individual trajectories. The asymptotic stability of motions of charged particles is checked for a different choice of the system parameters and their relations.

The new NICA (Nuclotron-based Ion Collider fAсility) accelerator complex being built at the Joint Institute for Nuclear Research (Dubna, Russia) is intended for experiments with 197Au79+ gold nuclei at energies in the range of 1–4.5 GeV/n. The RF system of the collider should provide the capture of bunches to be injected from the nuclotron, the accumulation of the necessary number of particles, their acceleration (if necessary), and the formation of bunches. For this, in each ring of the collider, three types of accelerating stations are used: one barrier station and two harmonic stations. The barrier station accumulates the particles and can used to accelerate them up to the energy of the experiment. The harmonic RF stations operating at the 22th and 66th harmonics of the revolution frequency are used for the formation of bunches. This paper describes the operating modes of the RF system and the design features of the RF stations.

One of the processes leading to the vacuum conditions degradation when working with a gold bare nuclei beam in the NICA Collider can be the electron clouds effect. Influence of electron cloud densities on the coherent tune shift of ion betatron oscillation in the Collider ring was investigated for different bare gold nuclei beam intensity, its energies and electron secondary emission yields from the Collider vacuum chamber. The pressure rise due to additional gas load and heat load caused by electron clouds are estimated.

The solutions of equations characterizing the dynamics of charged particles in electromagnetic Penning–Malmberg traps with a rotating transverse electric field are presented and analyzed. The equations of motion are transformed in a way that makes it possible to distinguish between the motions of magnetron and cyclotron particles, reduce the system of equations to a stationary one, and conclude that asymptotically Lyapunov stable solutions of these equations are lacking in a certain parameter interval. This allows one to optimize the confinement of charged particles in such traps.

The use of RF buckets for ion storage in the NICA is discussed. After storage, the RF2 system bunches the beam at the 22nd harmonic. Under cooling and an adiabatic increase in the RF2 voltage, a bunch shortens to the point when it fits into the separatrix of the 66th harmonic. The bunch is then recaptured into the separatrix of the 66th harmonic of the RF3 system. Ion bunches with the needed experimental parameters are formed under further cooling and an adiabatic increase in the RF3 voltage. Parasitic collisions occur at the interaction point in the process of ion storage and bunching.

A method for forming a continuous flux of monochromatic positrons with a controlled time of arrival at the target, independent of the start time in a limited start time interval. Such an ordered positron (OPF) flux allows one to construct an experimental setup for studies of solid matter structure by positron annihilation spectroscopy (PAS) in its most efficient version—the Positron Annihilation Lifetime Spectroscopy (PALS). Simultaneously, by varying the potential of the target, one can control the energy of the positrons on the target and, accordingly, the depth of their penetration into the sample under study, measuring the distribution of defects in depth with high resolution. The research has been performed at the Dzhelepov Laboratory of Nuclear Problems, JINR and has been presented at the XII International Seminar in memory of V.P. Sarantsev, 2017, Alushta, Crimea, Russia.

A new accelerator complex is being constructed at the Joint Institute for Nuclear Research as a part of the Nuclotron-based Ion Collider fAcility (NICA) project. The goal is to conduct experiments with colliding ion beams (at the first stage of the project) and colliding polarized proton/deuteron beams (at the second stage). Transport beam channels and the systems of beam injection and extraction for synchrotrons and collider rings are an important connecting link for the whole accelerator facility. The design of the primary beam-transport channels and injection/extraction systems are presented. Special attention is paid to various aspects of dynamics of beams in their transfer between the NICA accelerators.

The NICA complex comprises the Booster and Nuclotron synchrotrons for accelerating particle beams to the required energy and the Collider machine, in which particle collisions are investigated. The experimental heavy-ion program deals with ions up to Au+79. The light-ion program deals with polarized deuterons and protons. Grouping of a beam coasting in an ion chamber is required in many parts of the complex. Beam grouping may effectively increase the longitudinal emittance and particle losses. To avoid these negative effects, various regimes of adiabatic grouping have been simulated and dedicated experiments with a deuteron beam have been conducted at the Nuclotron machine. As a result, we are able to construct and optimize the beam-grouping equipment, which provides a capture efficiency near 100% either retaining or varying the harmonic multiplicity of the HF system.

The effect of a rotating electric field on the electrons and positrons accumulated in a Penning–Malmberg–Surko trap (increase in the lifetime of the particles and the efficiency of their accumulation, reduction of the transverse dimensions of the bunch of accumulated particles) is studied. New results of the basic character related to the resonance effect of a rotating field on the accumulation of particles at low intensities are obtained. The transition region to the high intensity bunches of accumulated particles is studied. A mechanism explaining the experimental results based on three-dimensional particle dynamics in the trap is proposed.

A project of the system of heavy-ion beam injection into the Booster synchrotron of the NICA accelerator complex developed at the Joint Institute for Nuclear Research (Dubna) is considered. The proposed system provides multivariant injection for accumulating beams with required intensity. The main methods of beam injection into the Booster are described. These are the methods of one-turn, multiturn, and multiple injections. The results of beam dynamics simulations are presented.

The paper investigates the problem of balance between the intrabeam scattering, electron cooling and radiative recombination processes in the NICA Collider working mode with using of electron cooling system. The reducing methods of radiative recombination influence due to electron cooling are discussed.

The experiment on measurement of secondary electron yield from surface of a stainless steel Kh189 sample covered with titanium nitride is performed at stand “Recuperator”. This work is related to known problem of electron clouds formation in a vacuum chamber by a propagating charge particle beam. An original method of secondary electron yield measurement was developed in this experiment. The obtained results allow one to estimate efficiency of coating nitride titanium.

The Low Energy Positron Toroidal Accumulator (LEPTA) at JINR proposed for generation of positronium in flight can be used for Positron Anihilation Spectroscopy (PAS). This is the sensitive method for microstructure studies of solid body. The structural defects such as vacancies, vacancy clusters and nanovoids with the size 0.1–10 nm can be detected. In this paper the progress in the development of PAS at LEPTA facility will be presented. The description of Doppler broadening of annihilation gamma line technique and the examples of results obtained on slow positron beam will be shown.

Principle of operation of barrier RF voltage systems that are used for stacking and acceleration of charged particles in proton synchrotrons and storage rings is presented. The description is based on two sample models of such systems: with rectangular and quasi-sinusoidal barriers. Two different methods are used for description of particle dynamics in synchrotrons with barrier RF voltage. The first method is “stepwise” analysis of particle motion in the “momentum-phase” space. This method allows to give a clear and simple description of physical principles of the method and to obtain its main properties in analytical form. However, this method is not always efficient. Therefore, a method of analysis of phase motion of particles in barrier systems based on solution of differential equations of phase motion is presented in the paper and is widely used in practice. This method allows both analytical calculations and numeric simulation, which is illustrated with the aid of supplied examples.

A scheme and a setup for the formation of the continuous monochromatic positron flux with a controllable time of arrival at the target independent of the launch time within a limited time interval are proposed. The method is described in [1]. The setup is intended for conducting experiments on measuring positron lifetime in matter using positron annihilation lifetime spectroscopy (PALS). This method allows types of defects to be discriminated in materials. In the proposed version, it is possible to vary the positron energy, which allows the distribution of defects over the sample depth to be analyzed. Schemes of periodic preset-shape RF voltage generation and positron lifetime measurement are discussed.

Based on results of works on the NICA/MPD (Joint Institute for Nuclear Research, Dubna) project, the possibility of designing a heavy ion linear accelerator with high-frequency quadrupole focusing both in the input part and in the main part of the accelerator is shown. Parameters of the linear 197Au31+ ion accelerator are presented. Special attention is paid to technical questions of calculating, designing, manufacturing, and tuning the accelerator.

New scientific program is proposed at Joint Institute for Nuclear Research (JINR) in Dubna aimed a study of hot and dense baryonic matter in the wide energy region from 2 GeV/amu to √s NN = 11 GeV, and investigation of nucleon spin structure with polarized protons and deuterons maximum energy in the c.m. 27 GeV (for protons). To realize this program the development of JINR accelerator facility in high energy physics has started. This facility is based on the existing superconducting synchrotron—Nuclotron. The program foresees both experiments at the beams extracted from the Nuclotron, and construction of ion collider—the Nuclotron-based Ion Collider fAcility (NICA).

Results from experimental studies of plasma storage in a Penning-Malmberg trap at the LEPTA facility are presented. The number of stored particles is found to increase substantially when using the so-called “rotating wall” method, in which a transverse rotating electric field generated by a cylindrical segmented electrode cut into four pairs is applied to the plasma 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 plasma storage are discussed.

Experimental data on rates for the radiative recombination of nuclei (from helium to uranium) and various ions in interaction with an electron beam in electron cooling systems are reviewed. An analysis of the experimental data has yielded the dependence of the radiative recombination rate on the relative electron energy appreciably differently than the theoretical models obtained earlier by H. Kramers and R. Schuch. In addition, it is shown that the radiative recombination rate of nuclei in the experiment depends on the transverse electron energy as T⊥−0.82,which is also different from the results of the calculations by the theoretical model proposed by M. Bell and J. Bell. Experimental data on the cooling of ions in intermediate charge states are analyzed and the dependence of the radiative recombination rate on the charge state of the ion (electron-shell configuration) is shown. For some ion charge states, the rate of the process is of a resonance character. Loss to radiative recombination in the electron cooling system of the NICA Booster is evaluated for the Au32+, Au33+, Au50+, and Au51+ ion beams. Limitations imposed on the Au79+ beam lifetime by radiative recombination in the electron cooling system of the NICA Collider are analyzed. Possible ways to decrease the radiative recombination rate of nuclei by selecting the parameters of the electron cooling system for the NICA Collider are proposed.

The project of the Low-Energy Particle Toroidal Accumulator (LEPTA) has been developed and is put into operation at the Joint Institute for Nuclear Research (Dubna). The LEPTA facility is a small positron storage ring equipped with an electron cooling system. The project positron energy is 2–4 keV. The main purpose of the facility is to generate an intense flux of positronium atoms (the bound state of the electron and positron). The LEPTA storage ring was commissioned in September 2004. The positron injector was designed in 2005–2010, and the beam transport channel was constructed in 2011. The experiments on electron and positron injection from the injector into the accumulator were started in August 2011. The results are reported here.

A heavy-ion collider, i.e., the Nuclotron-based Ion Collider Facility (NICA), is being developed at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The aim of this project is to construct a new accelerator complex for conducting experiments with colliding ion beam (at the first stage of the project) and with polarized proton and deuteron beams (at the second stage). The NICA accelerator complex will consist of two linear accelerators, two synchrotrons, two collider rings, and beam transportation lines. The magnetic lattice and diagnostic and correction systems for the NICA beam transportation lines are described in this report.

A high-voltage electron cooling system (ECS) with electron energy reaching 2.5 MeV for the NICA collider is being designed at the Joint Institute for Nuclear Research. The ECS is being developed in correspondence with the available experience in manufacturing similar systems from around the world. The main feature of this design is the use of two cooling electron beams (one beam per collider ring); electrons are accelerated and decelerated by a common high-voltage generator. A conceptual project of high-voltage ECS has been developed. The cooler consists of three tanks filled with SF6 gas under pressure. Two of them contain electron-beam forming systems; each system consists of two electron guns, two electron collectors, and accelerating-decelerating tubes placed in a longitudinal magnetic field generated by a solenoid. The third tank contains a high-voltage generator based on the voltage-multiplying circuit.

The Nuclotron-based Ion Collider Facility (NICA) is a new accelerator complex under construction at the Joint Institute for Nuclear Research (JINR) for experiments with colliding beams of heavy ions up to gold at energies as high as 4.5 × 4.5 GeV/u aimed at studying hot and dense strongly interacting nuclear matter and searching for possible indications of the mixed phase state and critical points of phase transitions. This facility comprises an ion source of the electron-string type, a 3-MeV/u linear accelerator, a 600-MeV/u superconducting booster synchrotron (Booster), a Nuclotron (upgraded superconducting synchrotron with a maximum energy of 4.5 GeV/u for ions with the charge-to-mass ratio Z/A = 1/3), and a collider consisting of two vertically separated superconducting rings with an average luminosity of 1027 cm−2 s−1 in an energy range over 3.0 GeV/u. Beam cooling is supposed to be used in two NICA elements, the Booster, and the collider rings. The Booster is intended for the storage of 197Au31+ ions to an intensity of about 4 × 109 particles; their acceleration to the energy 600 MeV/u, which is sufficient for the complete stripping of nuclei (an increase in the injection energy and the charge state of ions makes the requirements for vacuum conditions in the Nuclotron less stringent); and the formation of the necessary beam emittance using the electron cooling system. Two independent beam-cooling systems, a stochastic one and an electron one, are supposed to be used in the collider. The parameters of the cooling systems, the optimum mode of operation for the collider, and the arrangement and design of the elements of the systems are discussed.

A new scientific program is proposed at the Joint Institute for Nuclear Research (JINR) in Dubna aimed at studies of hot and dense baryonic matter in the wide energy range from 2 GeV/u kinetic energy in fixed target experiments to \(\sqrt {s_{NN} } = 4 - 11\) GeV/u in the collider mode. To realize this program the development of the JINR accelerator facility in high-energy physics (HEP) has been started. This facility is based on the existing superconducting synchrotron—the Nuclotron. The program foresees both experiments at the beams extracted from the Nuclotron, and the construction of a heavy-ion collider—the Nuclotron-based Ion Collider fAcility (NICA) which is designed to reach the required parameters with an average luminosity of L = 1027 cm−2 s−1.

The project of Nuclotron-based Ion Collider fAcility NICA/MPD (+MultiPurpose Detector) under development at JINR (Dubna) is presented. The general goals of the project are providing of colliding beams for experimental studies of both hot and dense strongly interacting baryonicmatter and search for the mixed phase and critical endpoint and spin physics in collisions of polarized protons (deuterons). The first program requires providing of heavy-ion collisions in the energy range of $$\sqrt {s_{NN} } = 4 - 11$$ GeV at average luminosity of L = 1 × 1027 cm−2 s−1 for 197Au79+. The polarized beams mode is proposed to be used in energy range of $$\sqrt s = 12 - 27$$ GeV (protons) at luminosity of L ≥ 1 × 1030 cm−2 s−1. The report contains description of the facility scheme and characteristics in heavy-ion operation mode, status and plans of the project development.

The project of a superconducting medical synchrotron for carbon therapy in the ion energy range from 140 to 400 MeV/n is discussed in this paper. This project is aimed at developing and building a medical synchrotron on the basis of superconducting technologies at JINR under the construction of the Nuclotron accelerator complex. A linear accelerator with alternating phase focusing is proposed for injecting carbon ion into the synchrotron, while it is planned to use a superconducting gantry weighing about 150 t for delivering radiation treatment to patients from all directions.

NICA is a new accelerator complex being constructed at the Joint Institute for Nuclear Research; the main task of this complex is to perform collider experiments for ion beams up to uranium with energies of up to 3.5 × 3.5 GeV/nucleon. This complex includes an electron string ion source, a 6 MeV/nucleon linear accelerator, a booster, the Nuclotron, and a collider with an average luminosity of 1027 cm2 s−1. The main tasks of the booster are to accumulate up to 4 × 109 197Au32+ ions, to accelerate to 600 MeV/nucleon (sufficient enough energy for completely stripping nuclei), to reduce the requirements of vacuum conditions for the Nuclotron, and to form the necessary beam emittance using an electron cooling system. The specific features of the NICA booster and the requirements for the basic systems of the synchrotron and their parameters are presented in this paper.

The main objective of the NICA project developed at the Joint Institute for Nuclear Research (JINR) is to conduct experimental studies with colliding heavy ion beams in an energy range of 1–4.5 GeV/nucleonucleon with luminosity on the level of 1 × 1027 cm−2 s−1. In this paper the operation regime of the collider injection chain providing the bunch with experimentally desirable parameters at the output of the Nuclotron is considered for gold ions as an example.

The Low Energy Particle Toroidal Accumulator (LEPTA), a positron storage ring with electron cooling, was constructed and put in operation at the Joint Institute for Nuclear Research (Dubna). The storage ring is a generator of directed beams of ortho-positronium (o-Ps) produced upon the recombination of the beam of positrons circulating in the storage ring with a single-pass electron beam. In 2004 the storage ring was put in operation with the circulating electron beam. The source of positrons of the positron injector was tested with a new radioactive source delivered from South Africa. The positron trap was put in operation for electrons. The electron cooling system was tested with a pulsed electron beam. The progress in commissioning LEPTA is described in this paper.

The Nuclotron superconducting synchrotron was constructed in 1987–1992 [1]; it is the world’s first synchrotron based on fast cycling “window frame” electromagnets with a superconducting coil. For a design field of dipole magnets of 2 T, the magnetic rigidity is 45 T m, which corresponds to the energy of heavy nuclei (for example, gold) of 4.5 GeV/nucleon. The Nuclotron accelerator complex is currently being upgraded (the Nuclotron-M project); this upgrade is considered a key part of the first stage of fulfilling the new Joint Institute for Nuclear Research (JINR) project: the Nuclotron-based Ion Collider fAcility and Multi-Purpose Detector (NICA/MPD). The most important task of this new project is the preparation of basic Nuclotron systems for its reliable operation as part of the NICA accelerator complex. Basic results of activity on the project, which started in 2007, are presented and the results of the last Nuclotron runs are analyzed.

JINR is an active participant in the massive new international project ILC. JINR physicists are taking part in several fields of activity in the International Linear Collider (ILC), such as work on the photo injector prototype, the design and construction of cryomodules, laser metrology, cryodiagnostics, etc. The Joint Institute is one of the potential candidates for hosting the ILC, near Dubna, Russia. The status and progress of the above topics are discussed in the report.

The interaction of the positronium with a magnetic field is investigated. The high-precision formulae for probabilities of ortho-and parastates of the positronium in the magnetic field are calculated with allowance for the difference between the magnetic moments of electron and positron in positronium and those of free particles. The results of these calculations are used for setting up the PALM experiment dedicated to the parapositronium lifetime measurement in vacuum.

A cryogenic source of slow monochromatic positrons based on 22Na radioactive isotope has been developed and produced at the Joint Institute for Nuclear Research. A monochromatic beam is formed from a continuous β+ spectrum with energies of 0–0.5 MeV using a solid neon moderator frozen onto a copper substrate that is cooled to temperatures of 5–7 K. The efficiency of condensation of neon onto the substrate is >99.8%. A slow positron beam with an intensity of 5.8 × 103 particles/s and a mean energy of 1.2 eV at a spectrum width of 1 eV has been extracted from a 22Na-based test source. The fraction of decelerated positrons is 1% of the total flux.

The project of the Low Energy Particle Toroidal Accumulator (LEPTA) is dedicated to the construction of a positron storage ring with electron cooling of positrons circulating in the ring. Such a specific feature of LEPTA automatically enables it to be a generator of positronium (Ps) atoms, which appear in the recombination of positrons with cooling electrons inside the cooling section of the ring. The project has the following goals: particle dynamics in the modified betatron, electron cooling with a circulating beam, positronium generation in flight, positronium physics, and feasibility of antihydrogen generation in flight. All key elements of the ring—the kicker, electron beam injection system, helical quadrupole, septum magnet—have been tested, and the expected design parameters have been achieved for these elements. The construction of LEPTA has been completed, and the circulating electron beam has been achieved. This paper discusses the issues of particle dynamics in such an accelerator, the results of numerical simulation and experimental findings of the research into beam dynamics, measurement of betatron number and beam lifetime.

The effect of electron clouds in NICA collider was analyzed first in 2008 at development of NICA CDR [1]. The simulation results were revised and renewed numbers are presented in this section. Both simulations were performed with ECLOUD code, version 3.3 [2].

An injector of monochromatic positrons for the low-energy positron accumulator (LEPTA) is being tested at the Joint Institute for Nuclear Research. The source of positrons is the radioactive source 22Na. At the output of the source, positrons are slowed down in a solid target. Frozen neon is used as a moderator. For this purpose, a system of cryocooling of the source and the neon supply line have been assembled. A method of detection of slow positrons has been developed and tuned. The first experiments with the frozen moderator have been performed. A continuous beam of slow positrons with an average energy of 1.2 eV and spectrum width of 1 eV has been obtained.

The BETACOOL program, developed by electron cooling group of the Joint Institute for Nuclear Research (JINR), is a set of algorithms based on common format of input and output files. The program is oriented toward simulation of the ion beam dynamics in a storage ring in the presence of cooling and heating effects. The version presented in this report includes three basic algorithms: simulation of root-mean-square (rms) parameters of the particle distribution function evolving in time, simulation of the distribution function evolution using the Monte Carlo method, and a tracking algorithm based on a molecular dynamics technique. The general processes investigated with the program are intrabeam scattering in the ion beam, electron cooling, and interaction with residual gas and an internal target.

An analysis is made of the reasons for the onset of a Penning discharge in electron-optical devices operating at moderate and high vacuum in the presence of an accompanying magnetic field. Methods of suppressing this discharge are recommended. The main results of tests to eliminate the Penning discharge in the test rig at the Joint Institute of Nuclear Research (Dubna) and in the CERN Low Energy Antiproton Ring (LEAR) (Geneva) are presented.

An experiment on measuring the secondary electron yield (SEY) of samples coated with titanium nitride (TiN2) is in progress at the Recuperator test bench at the Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research. This work is related the problem of electron-cloud formation in the vacuum chambers of accelerators and is of practical importance for the NICA project. The results of the experiment on the SEY measurement will make it possible to choose the most appropriate material for coating the vacuum chamber. In this experiment samples of stainless steel with titanium nitride coating and without any coating are compared.

The injector of the low energy positrons for accumulator LEPTA is being assembled at JINR. The key elements of the injector have been tested. The cryogenic source of slow positrons has been tested with a test isotope 22 Na of the initial activity of 0.8 MBk. The continuous slow positron beam intensity of 5.8 · 10 3 s −1 with average energy of 1.2 eV and width of a spectrum 1 eV has been obtained. The achieved moderator efciency is about 1%. The accumulation process in the positron trap was investigated with electronux. Th e lifetime of the electrons in the trap, τlife 80 sa nd capture efciency e ∼ 0.4 have been obtained. The maximum number of the accumulated particle was Nexp =2 · 10 8 at the initialux of 5 · 10 6 e − /s. ‚ �ˆŸˆ § ¢¥·I ¥E¸O ¸iμ·± ¨³¶E²O¸´μ£μ ¨´|¥± Eμ· ¶μ§¨E·μ´μ¢ ´¨§±μ° O´¥·£¨¨ ¤²O E¸E - ´μ¢±¨ LEPTA. �·μ¢¥¤¥´μ O±¸¶¥·¨³¥´E ²O´μ¥ ¨ ¸¸²¥¤μ¢ ´¨¥ · iμEO μ¸´μ¢´OI E§²μ¢ ¨´|¥±Eμ· . ˆ¸¸²¥¤μ¢ ´ · iμE ±·¨μ£¥´´μ£μ ¨¸EμI´¨± ¶μ§¨E·μ´μ¢ ¸ E¥¸Eμ¢O³ ¨§μEμ¶μ³ 22 Na, ±E¨¢´μ¸EOO 0,8 Œ±. �μ²EI¥´ ¶EIμ± ³¥¤²¥´´OI ¶μ§¨E·μ´μ¢ ¨´E¥´¸¨¢´μ¸EOO 5,8 · 10 3 c −1 ¸μ ¸·¥¤´¥° O´¥·£¨¥° 1,2 O‚ ¶·¨ I¨·¨´¥ ¸¶¥±E· 1 O‚. "μ²O § ³¥¤²¥´´OI ¶μ§¨E·μ´μ¢ ¸μ¸E ¢¨² 1% μE ¶μ²´μ£μ ¶μ- Eμ± . �·μ¢¥¤¥´μ ¨¸¸²¥¤μ¢ ´¨¥ ¶·μI¥¸¸ ´ ±μ¶²¥´¨O I ¸E¨I ¢ ²μ¢EI±¥ ´ O²¥±E·μ´ I. ‚ ·¥§E²OE E¥ μ¶E¨³¨§ I¨¨ ¶ · ³¥E·μ¢ ²μ¢EI±¨ ¤μ¸E¨£´EEμ ¢·¥³O |¨§´¨ ´ ±μ¶²¥´´OI O²¥±E·μ´μ¢ τlife 80 ¸, OEE¥±E¨¢´μ¸EO § I¢ E e ∼ 0,4, IEμ ¸μμE¢¥E¸E¢E¥E ´ ¨²EII¨³ ·¥§E²OE E ³, ¶μ²EI¥´´O³ ¢ ²μ- ¢EI± I ¶μ¤μi´μ£μ E¨¶ . �·¨ OEμ³ ³ ±¸¨³ ²O´μ¥ I¨¸²μ ´ ±μ¶²¥´´OI I ¸E¨I Nexp =2 · 10 8 ¶·¨ ¶¥·¢μ´ I ²O´μ³ ¶μEμ±¥ 5 · 10 6 e − /¸.

The results of testing a cryogenic source of slow monochromatic positrons based on the 22Na isotope, designed and constructed at JINR, are presented. A solid neon moderator was used to generate a monochromatic beam from the continuous β+ spectrum of 0–0.5 MeV, with solid neon being frozen to the base layer, which is cooled to the temperature of 5–7 K. Test source of the 22Na isotope allows the forming of a slow positron beam of intensity 5.8 × 103 part./s and the average energy 1.2 eV at a spectrum width of 1 eV. The efficiency of moderation is 1% of the total positron flux.