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The first beam of 84Kr¹⁴⁺ ions was accelerated in the DC-280 on December 26, 2018 and extracted to the ion transport channel on January 17, 2019. In March 2019, beams of accelerated 84Kr⁺14 ions with intensity of 1.36 pmkA and 12C⁺2 ions with and intensity of 10 pmkA were extracted from the DC-280 to the beam transport channel with energy about 5.8 MeV/nucleon. In 2020-2021 years, beams of 48Ca⁷⁺,10+ ions with intensity up to 10,6 pmkA were accelerated and 7,1 pmkA were extracted from the DC-280 to the beam transport channel with energy about 4,51 - 5,29 MeV/nucleon. In 2021 year, beams of accelerated 52,54Cr¹⁰⁺ ions with intensity up to 2,5 pmkA were extracted from the DC-280 to the beam transport channel with energy about 5,05 MeV/nucleon and beams of 48Ti⁷⁺ with intensity up to 1pmkA and with energy about 4,94 MeV/nucleon The main task of the new accelerator is implementation of the long-term program of researches on the SHE Factory aimed on synthesis of new elements (Z>118) and detailed studying of nuclear- physical and chemical properties of earlier opened 112-118 ones., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The High Intensity heavy-ion Accelerator Facility (HIAF) is under constructed at IMP in China. The HIAF main feature is rapid acceleration of ions in the booster synchrotron ring (BRing) with the ramping rate up to 12 T/s. The challenges are related to the systems RF cavities, dipole power supplies, vacuum etc. Works on key prototypes of the HIAF machine are ongoing at IMP. In this paper, the test results of the power supplies, RF cavities and vacuum chambers are presented. As the construction of the HIAF facility has started, an overview of the hardware developments will also be reported., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

At the present time, the activities on creation of the new heavy-ion isochronous cyclotron DC140 are carried out at Joint Institute for Nuclear Research. DC140 facility is intended for SEE testing of microchip, for production of track membranes and for solving of applied physics problems. Cyclotron will produce accelerated beams of ions A/Z= 5 - 5.5 and 7. 5 - 8.25 with a fixed beam energy 4.8 MeV/n and 2.124 MeV/n respectively. The variation of operation modes is provided by changing of magnetic field in the range 1.4T - 1.55T with fixed generator frequency 8.632 MHz. In this report, the results of design and simulation of the beam acceleration and extraction are presented., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

New accelerator complex is being constructed by Joint Institute for Nuclear Research (Dubna, Russia) in frame of Nuclotron-based Ion Collider fAcility (NICA) project. The NICA layout includes new Booster and existing Nuclotron synchrotrons as parts of the heavy ion injection chain of the NICA Collider as well as beam transport lines which are the important link for the whole accelerator facility. Designs and current status of beam transfer systems in the beginning part of the NICA complex, which are partially commissioned, are presented in this paper., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research continues the works under creating of FLNR JINR Irradiation Facility based on the cyclotron DC140. The facility will have three experimental beam lines for SEE testing of microchips, for production of track membranes and for solving of applied physics problems. The injection into cyclotron will be realized from the external room temperature 18 GHz ECR ion source. The systems of DC140 cyclotron such as axial injection, main magnet, RF- and extraction systems and beam lines are the reconstruction of the DC72 cyclotron ones. The acceleration in DC140 cyclotron is carried out for two values of harmonic number h = 2,3 of heavy ions with mass-to-charge ratio A/Z within two intervals 5 - 5.5 and 7.5 - 8.25 up to two fixed energies 2.124 and 4.8 MeV per unit mass, correspondingly. The intensity of the accelerated ions will be about 1 pmcA for light ions (A86) and about 0.1 pmcA for heavier ions (A>132). The design of the axial injection system of the DC140 cyclotron is presented in this report., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

A superconducting magnet system for a 28 GHz ECR ion source DECRIS-SC2 was studied in order to select its parameters and optimize performance. Parametric magnetic models were performed for two design configurations, conventional ("sextupole-in-solenoid") and reversed ("solenoid-in-sextupole"). In the "sextupole-in-solenoid" design the racetrack coils of the sextupole magnet used for radial plasma confinement are located inside the solenoids producing the axial field. In the "solenoid-in-sextupole" design the coils arrangement is reversed. For both configurations, electromagnetic effect the booster and the steel poles on the magnet performance was investigated from the point of view critical parameters of the system ’ currents, fields, and forces. Results of the parametric computations were used to optimize the geometry and sizes of the magnet as well as the magnetic shield, the booster, and the poles. For better reliability and validation of the result, computations were performed with two magnetostatic codes, KOMPOT and KLONDIKE, utilizing the differential and integral formulations, respectively. A comparison of the obtained parameters was used to select the candidate magnet configuration for further design and manufacture., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The Nuclotron-based Ion Collider fAcility (NICA) is un-der construction in JINR. The NICA goals are providing of colliding beams for studies of hot and dense strongly interacting baryonic matter and spin physics. The NICA complex injection facility consists of four accelerators: Alvarez-type linac LU-20 of light ions up to 5 MeV/u; heavy ion linac HILAC with RFQ and IH DTL sections at energy 3.2 MeV/u; superconducting Booster synchrotron at energy up 578 MeV/u; superconducting synchrotron Nuclotron at gold ion energy 3.85 GeV/u. In the nearest future the old LU-20 will be substituted by a new light ion linac for acceleration of 2 < A/z < 3 ions up to 7 MeV/u with additional two acceleration sections for protons, first IH section for 13 MeV and the second one - superconducting for 20 MeV. The status of NICA injec-tion facility is under discussion., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The main activities of Flerov Laboratory of Nuclear Reactions, following its name - are related to fundamental science, but, in parallel, plenty of efforts are paid for practical applications. For the moment continues the works under creating irradiation facility based on the cyclotron DC140 which will be dedicated machine for applied researches in FLNR. The beam transport system will have three experimental beam lines for testing of electronic components (avionics and space electronics) for radiation hardness, for ion-implantation nanotechnology and for radiation materials science. The DC140 cyclotron is intended for acceleration of heavy ions with mass-to-charge ratio A/Z within interval from 5 to 8.25 up to two fixed energies 2.124 and 4.8 MeV per unit mass. The intensity of the accelerated ions will be about 1 pmcA for light ions (A86) and about 0.1 pmcA for heavier ions (A>132). The following elements are used to extract the beam from the cyclotron: electrostatic deflector, focusing magnetic channel, Permanent Magnet Quadrupole lens and steering magnet. The design of the beam extraction system of DC140 cyclotron are presented in this report., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The new linac for A/Z = 8, output energy 4 MeV/u and 10 mA current is under development at NRC "Kurchatov Institute" - ITEP. The linac consists of Radio-Frequency Quadrupole (RFQ) and two sections of Drift Tube Linac (DTL). The 40 MHz 11 meters long RFQ is based on a 4-vane structure with magnetic coupling windows. The paper presents results of tuning radio-frequency (RF) RFQ parameters., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

Injector of NICA accelerating facility based on the Heavy Ion Linear Accelerator (HILAC) is aimed to inject the heavy ions having atomic number A~200 and ratio A/Z - 6.25 produced by ESIS ion source accelerated up to the 3.2 MeV for the injection into superconducting synchrotron (SC) Booster. The project output energy of HILAC was verified on commissioning in 2018 using the beams of carbon ions produced with the Laser Ion Source and having ratio A/Z=6 that is close to the project one. Beams of He¹⁺ ions were injected into Booster in its first run and accelerated in 2020. In 2021 ions of Fe¹⁴⁺ produced with the LIS were injected and accelerated up to 200 MeV/u. Beam formation of Fe ions and perspectives of using LIS for the production the ions with high atomic mass A and ratio A/Z matching to HILAC input parameters are described., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

This paper presents the results of the calculation of the magnetic system of the cyclotron for accelerating of multicharged ions developed at NIIEFA JSC. The cyclotron complex is designed to generate ions with a mass-to-charge ratio in the range A/Z= 3/7, accelerate them to energies in the range of 7.5-15 MeV per nucleon. The cyclotron electromagnet has a four-sector structure, with a pole diameter of 4 m. Radial coils placed on the poles under the sectors are designed to adjust the magnetic field for providing isochronous acceleration conditions for different ions. A group of azimuthal coils designed to correct the first harmonic of the magnetic field and to center the orbits of the accelerated ion, as well as to ad-just the position of the axial symmetry plane of the magnetic field is located on the sectors. The required magnetic field topology for ion acceleration was formed in the induction range of 1.29-1.6 T. Calculations were per-formed for the 1/8 part of the electromagnet. A mode was chosen in which the dependence of induction on the radius, which provides isochronism, is realized due to the shape of "iron". For this mode with an induction in the center of 1.44 T, the shape of side plates, plugs, and sec-tor chamfers was determined. The currents in radial coils and the main dynamic characteristics of the cyclotron magnetic field for ion acceleration in the energy control range were calculated using the obtained magnetic field maps., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The JSC "NIIEFA" is designing a cyclotron system intended to accelerate ions with a mass-to-charge ratio of 3-7 in the energy range of 7.5-15 MeV per nucleon. The variety of ions, the range of changes in their energy, and the intensity of the beams provide conditions for a wide range of basic and applied research, including for solving a number of technological tasks. The cyclotron electromagnet has an H-shaped design with a pole diameter of 4 meters and a four-sector mag-netic structure. In the basic mode, the dependence of the induction on the radius corresponding to the isochronous motion is realized by turning on the main coil only through the shape of the central plugs, sector side plates, and sector chamfers. For other modes of isochronous ac-celeration, the current in the main coil is changed and cor-rection coils are tuned. The resonance system consists of two resonators with an operating frequency adjustable from 13 to 20 MHz. The final stage of the RF generator is installed close to the resonator and is connected to it by a conductive power input device. The external injection system generates and separates ions with a given A/z ratio. The injection energy is chosen such that the Larmor radius is constant, which allows us-ing an inflector of unchanged geometry for the entire list of ions. The transportation system forms beams of accelerated ions with specified parameters and delivers them to sample irradiation devices. Computer control of the cyclotron is provided., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

Third-order resonance slow extraction from synchrotron is the most common use extraction method for external target experiments nuclear physics, proton and heavy ion therapy, since it can provide relatively stable beams in long time. The principle of third-order resonant slow extraction is intentionally exciting the third-order resonance by controlling detuning and sextupole strength to gradually release particles from inside to outside stable separatrix. BINP develop the ion synchrotron for wide range of technological application. The present paper describes slow extraction method with exiting betatron oscillations by the transverse RF-field. Such extraction technique provides stable current extraction for entire extraction time., Proceedings of the 27th Russian Particle Accelerator Conference, RuPAC2021, Alushta, Russia

The radiation environment in space has severe adverse effects on electronic systems. To evaluate radiation sensitivity, electronics are tested on earth with different types of irradiation sources. Cosmic rays (CR) are the most difficult to simulate on earth, because CR can have energies up to 1020 eV, with a flux maximum of around 1 GeV/n. However, only particles with energies up to several GeV/nucleon are relevant for radiation effect testing of space electronics due to the negligible fluxes beyond. Traditionally single-event effects of these particles were simulated with heavy ions having energies of only a few MeV/n because for “large” devices only the energy loss, often referred to as linear energy transfer (LET), had to be matched. Heavy ions of such high energies can produce secondary particles through nuclear interactions which can induce additional ionization that leads to adverse effects. The need to investigate these effects has grown since electronic devices now incorporate heavier elements (e.g., Cu, W) close to sensitive elements which can have significantly larger nuclear cross sections than in the 1 to 10 MeV/n energy regime. At the moment there is a large trend in the space community to increasingly use commercial off-the-shelf (COTS) electronic devices. One of the reasons is that many challenging space applications can only be met with COTS devices because there are simply no space-qualified devices [often referred to as High Reliability (HiRel)] available with the necessary performance. Another trend in the evolution of Si-based microelectronic integrated circuits is to create 3-dimensional (3D) structures. There are already commercially available 3D NAND-Flash devices [i.e., a type of non-volatile computer memory that uses floating-gate transistors that resembles a NAND (NOT-AND) gate] with several tens of active layers stacked on top of each other. These structures cannot be tested with low energy ions, due to the large depths of the sensitive volumes alone. For radiation tests ion beams are needed that provide constant LET over the whole stack (> 128 layers). In addition, e.g., in systems in a package, one finds several dies stacked on top of each in a single package. To investigate the aforementioned device types, the beam has to be able to penetrate through all the dies.

Proceedings of RUPAC2018 Russian Particle Accelerator Conference 26th Russian Particle Accelerator Conference, RUPAC2018, Brotvina, Russia, 1 Oct 2018 - 5 Oct 2018; JACoW Publishing, Geneva, Switzerland 13 pp. (2018). doi:10.18429/JACOW-RUPAC2018-WEPSB13, Recently the first section of a standalone superconducting (sc) continuous wave (cw) heavy ion Linac as a demonstration of the capability of 217 MHz multi gap Crossbar H-mode structures (CH) has been commissioned and extensively tested with beam at GSI. The demonstrator set up reached acceleration of heavy ions up to the design beam energy and beyond. The required acceleration gain of 0.5 MeV/u was achieved with heavy ion beams even above the design mass to charge ratio at maximum available beam intensity and full beam transmission. This contribution presents further development and optimization of the HIM/GSI cw-Linac., Published by JACoW Publishing, Geneva, Switzerland

The design of two beam lines for ion transportation from cyclotron DC280 to Gas Filled Separators (GSF) is presented. The beam lines include commutating magnet with variable magnetic field induction up to 1.5 T that gives the possibility to bend ion beams in five directions providing ion transportation through beam lines to five experimental setups. The beam focusing in the beam lines is provided by set of quadrupole lenses having the gradients up to 7.7 T/m. The beam lines are intended for the efficient ion transportation of elements from Helium to Uranium with the atomic mass to charge ratio in the range of 4-7.5 at energies from 4 up to 8 MeV/amu. The ion beam power will reach the value about 3 kW. The water cooled current aperture diaphragms will be installed into all beam lines to prevent the tube damage. The beam diagnostics consists of the Faraday caps (FC), slit collimators, sector aperture diaphragms and ionization beam profile monitors. A new structure of the beam line #3 and calculation results for 48Ca⁹⁺ and 48Ca⁷⁺ ion beam transportation from the extraction point to the new gas-filled separator GFS2 are listed. In addition, a new structure of the beam line #4 and calculation results for 48Ca⁸⁺, 50Ti⁸⁺, and 54Cr⁹⁺ ion beam transportation from the extraction point to the new GFS3 are presented., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

New accelerator complex is constructed by Joint Institute for Nuclear Research (Dubna, Russia) in frame of Nuclotron-based Ion Collider fAcility (NICA) project. The NICA layout includes new 600 MeV/u Booster and existing Nuclotron synchrotrons as parts of the heavy ion injection chain of the NICA Collider as well as transport beam lines which are the important link for the whole accelerator facility. Designs and current status of beam transfer systems of the NICA complex are presented in this paper., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

The Krion-6T ion source is an electron string ion source (ESIS) of multicharged ions. It will be used as an ion source for the heavy ion linac at the NICA project, but has been tested on an existing injection facility - Alvarez-type linac LU-20 with new RFQ type fore-injector. The transverse emittance measurements were carried out on the initial part of channel (IPC) of the low energy beam transport (LEBT) channel, between the ion source and RFQ fore-injector by pepper-pot method. Beams of multicharged Argon and Xenon ions are observed. Measurements of the profile and emittance were performed over several energies for each type of ions. The results of the measurement are presented, and some points of emittance calculations are considered., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

The prospective opportunity for high-temperature plasma generation by opposing collision of accelerated to 10-20 keV/amu cluster ion beams of hydrogen isotopes within the rectilinear section of magnetic trap was considered earlier in ITEP. It showed the aggregate deuteron (or tritium) atom per charge unit in accelerated cluster ions may consider a possibility to create the thermonuclear fuel mass up to values when the mutual retardation of all the nucleons in colliding beams. In the present work some examples of earlier created RF accelerating systems for heavy ion linac may be considered as prototypes for study of features and some off-beatings of heavy cluster ions of hydrogen isotopes for plasma generation are discussed. Some features of basic possibility for creation such kind of accelerator systems for cluster ion with mass-to-charge ratio of 10³-10⁴ are considered., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

Design and construction of CW high intensity linacs are important issues of worldwide accelerator technology development. RFQ linacs are useful for large scale research facilities such as SNS, ADS and FRIB. RFQ are necessary to use for low-energy nuclear and radioactive ion physics (e.g., DERICA - Dubna Electron - Radioactive Ion Collider fAcility project, Dubna, Russia). Some solutions are applied for RFQ to oper-ate in CW mode. The decrease of accelerating field and of RF field overvoltage is one of that solutions. Maximal field for CW RFQ is traditionally limited by 1.3-1.5 of the Kilpatrick criterion value comparatively of 1.8-2.0 for the pulse mode. But the thermostabilization of the RFQ cavity is very important problem. Accelerating structure undergoes high thermal loads for operating a CW mode, therefore water cooling system is needed. In this report a selection of an optimal resonator shape and water cooling system con-figuration was done and thermodynamics simulation results will presented., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

Measurement of absolute Dee voltage results of the isochronous cyclotron U-400M at FLNR JINR by the X-ray technique will be presented. Measurements were made at the following frequencies of the resonance system: 12.8, 13.317, 15.012, 15.1 and 17.5 MHz. The modeling of X-ray spectrum was carried out by the software package FLUKA to accurately determine the maximum energy of X-ray spectrum. An influence of the absolute Dee voltage was estimated by the program Center., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

The new accelerator complex Nuclotron-based Ion Collider fAcility (NICA) is under development and construction at JINR, Dubna now. This complex is assumed to operate using two injectors: the Alvarez type linac LU-20 as injector of light ions, polarized protons and deuterons and a new linac HILAc - injector of heavy ions beams. The modernization of Alvarez-type linac began in 2016 by commissioning of new RFQ foreinjector, and in 2017 the new buncher in front of linac has been installed. The first Nuclotron run with new buncher was performed in January 2018 with beams of Xe+, Ar+ and Kr+. The beam produced by KRION-6T ion source were successfully injected and accelerated in the Nuclotron ring during the last run #55. Main results of the last Nuclotron run and plans for future development of NICA injection complex are presented in this paper., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

There are considered acceleration of few types multicharged ions with different A/Z ratio in single accelerating RFQ channel without outer focusing magnetic field. RFQ may be independent accelerator or as part of injection system into DTL of high energy. There are considered compact RFQ with high operating frequency (for example frequencis of P-diapason). So magnetic focusing is absent mathematical methods of control theory are used for optimization of RFQ vane geometry to obtain exit beam parameters suitable for further acceleration. It is possible separate acceleration a few type of ions in single RFQ channel or simultaneous acceleration if (case of heavy ions) ion currents are very small., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

Status of JINR FLNR cyclotrons and plans of their modernization together with plans on creation of new facilities will be reported. At present, three cyclotrons: U400, U400M and IC100 and MT-25 microtron are under operation at the JINR FLNR. U400 and U400M are the basic FLNR facilities that both are under operation is about 12000 hours per year. The U400 (pole diameter of D=4 m) was designed to accelerate ions from B to Bi up to 19 MeV/u. U400 reconstruction is planned. The U400M cyclotron (D=4 m) is used to accelerate ions from Li to Xe up to 60 MeV/u. U400M modernization is planned. The IC100 accelerator (D=1m) is used for applied researches with Ar, Kr and Xe ions at energy of 1.2 MeV/u. Creation of the dedicated DC-130 cyclotron (D=2m) with ion energies of 4.5 and 2 MeV/u is planned on the base of U200 cyclotron. The Super Heavy Element Factory (SHE factory) is the new FLNR JINR project. The DC-280 cyclotron (D=4 m) is the basic facility of the SHE factory, which will accelerate ions with energies 4 - 8 MeV/u cyclotron at intensities up to 10 pmkA for ion masses over A=50. The main systems of the DC-280 were assembled and tested, the cyclotron is preparing for commissioning., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

During operation of heavy ion accelerators a significant pressure rise has been observed when the intensity of the high energy beam was increased. The cause for this pressure rise is ion induced desorption, which is the result when beam ions collide with residual gas molecules in the accelerator, whereby they undergo charge exchange. Since the change in charge state will affect the bending radius of the particles after they have passed a bending magnet, they will not follow the required trajectory but instead collide with the vacuum chamber wall and gas are released. For the Future GSI project FAIR (Facility for Antiproton and Ion Research) there is a need to upgrade the SIS18 synchrotron in order to meet the requirements of the increased intensity. The aim of this work was to measure the desorption yields, η, (released molecules per incident ion) from materials commonly used in accelerators: 316LN stainless steel, Cu, Etched Cu, gold coated Cu, Ta and TiZrV coated stainless steel with argon and uranium beams at the energies 5-100 MeV/u. The measurements were performed at GSI and at The Svedberg Laboratory where a new dedicated teststand was built. It was found that the desorption yield scales with the electronic energy loss to the second power, decreasing for increasing impact energy above the Bragg Maximum. A feasibility study on the possibility to use laser refractometry to improve the accuracy of a specific throughput system was performed. The result was an improvement by up to 3 orders of magnitude, depending on pressure range.

The GANIL beam intensity measurement System enables tuning and control of the accelerator system. All along the ion beam transport line, the intensity is measured continuously with low frequency current transformers. The performance as optimized today is not satisfactory to precisely determine the accelerator efficiency on-line. A first study showed that the only sensors usable at GANIL are sensors sensitive to magnetic field (current transformers) and to electric field (capacitive probes). The theoretical study searched to predict the output of these types of sensors and enabled to define a signal treatment which corresponds to the specifications. For every sensor, this calculation is validated experimentally. Moreover this study raised the problem of calibration. The different tests completed allowed a definition of the real characteristics of the current measurements and a choice of the appropriate system.; La mesure de l'intensité du faisceau du GANIL (Grand Accélérateur National d'Ions Lourds, Caen) est un moyen de régler et surveiller l'accélérateur. Tout le long des lignes de transport du faisceau d'ions, l'intensité est continûment mesurée à l'aide de transformateurs d'intensité basse fréquence. Bien qu'optimisées, les performances ne sont pas satisfaisantes pour déterminer avec précision les rendements de l'accélérateur. Une étude préliminaire a permis de montrer que les seuls capteurs envisageables au GANIL sont des capteurs sensibles au champ magnétique (transformateur d'intensité) et au champ électrique (sonde capacitive). L'étude théorique cherchant à connaître la tension de sortie de ces deux types de capteurs en fonction des caractéristiques du faisceau (intensité, forme, vitesse…) permet de définir un traitement du signal qui répond aux spécifications visées. Pour chaque dispositif, ces calculs sont validés expérimentalement. Par ailleurs, le problème d'étalonnage de la mesure en ligne ou hors ligne a été soulevé. Une optimisation de la chaîne de mesure est présentée en fonction des spécificités visées. Les différents tests ont permis de dégager les réelles caractéristiques de la mesure d'intensité et de choisir un dispositif approprié.

The GANIL beam intensity measurement System enables tuning and control of the accelerator system. All along the ion beam transport line, the intensity is measured continuously with low frequency current transformers. The performance as optimized today is not satisfactory to precisely determine the accelerator efficiency on-line. A first study showed that the only sensors usable at GANIL are sensors sensitive to magnetic field (current transformers) and to electric field (capacitive probes). The theoretical study searched to predict the output of these types of sensors and enabled to define a signal treatment which corresponds to the specifications. For every sensor, this calculation is validated experimentally. Moreover this study raised the problem of calibration. The different tests completed allowed a definition of the real characteristics of the current measurements and a choice of the appropriate system., La mesure de l'intensité du faisceau du GANIL (Grand Accélérateur National d'Ions Lourds, Caen) est un moyen de régler et surveiller l'accélérateur. Tout le long des lignes de transport du faisceau d'ions, l'intensité est continûment mesurée à l'aide de transformateurs d'intensité basse fréquence. Bien qu'optimisées, les performances ne sont pas satisfaisantes pour déterminer avec précision les rendements de l'accélérateur. Une étude préliminaire a permis de montrer que les seuls capteurs envisageables au GANIL sont des capteurs sensibles au champ magnétique (transformateur d'intensité) et au champ électrique (sonde capacitive). L'étude théorique cherchant à connaître la tension de sortie de ces deux types de capteurs en fonction des caractéristiques du faisceau (intensité, forme, vitesse…) permet de définir un traitement du signal qui répond aux spécifications visées. Pour chaque dispositif, ces calculs sont validés expérimentalement. Par ailleurs, le problème d'étalonnage de la mesure en ligne ou hors ligne a été soulevé. Une optimisation de la chaîne de mesure est présentée en fonction des spécificités visées. Les différents tests ont permis de dégager les réelles caractéristiques de la mesure d'intensité et de choisir un dispositif approprié.

This study is related to the SPIRAL project. This facility uses a cyclotron to accelerate radioactive ion beams produced in a thick target by the Grant Accelerateur National d'Ions Lourds primary beam. The low intensity of radioactive beams and the mixing of several species imply special tuning methods and associated diagnostics. Also, a cyclotron and the beam line will be used to switch from this tuning beam to the radioactive one. We present a theoretical study and a numerical simulation of the tuning of five radioactive beams using three different methods. the beam dynamic is performed through the injection beam line and the cyclotron up to the electrostatic deflector. Within the frame of these methods we have described all the SPIRAL beam diagnostics. Construction and test of a new low intensity diagnosis based on a plastic scintillator for phase measurement inside the cyclotron is described in details., Cette étude s'inscrit dans le cadre du projet SPIRAL qui consiste à produire, puis à l'accélérer avec un cyclotron, des faisceaux d'ions radioactifs créés dans une cible épaisse par le faisceau primaire du Grand Accélérateur National d'Ions Lourds. La faible intensité de ces faisceaux radioactifs et la présence de polluants d'intensité égale ou supérieure à celle du faisceau désiré implique la mise au point de nouvelles méthodes de réglage et des diagnostics qui y sont associés. Ainsi, l'ensemble du post-accélérateur sera préréglé sur un faisceau d'ions stables, différentes méthodes permettant ensuite de passer ce cet ion stable à l'ion radioactif désiré. Nous présentons une étude théorique de ce processus ainsi qu'une simulation numérique détaillée du réglage de cinq faisceaux radioactifs différents à l'aide de trois méthodes. Le comportement du faisceau est simulé dans la ligne d'injection et dans le cyclotron jusqu'au déflecteur électrostatique d'ejection. Nous décrivons aussi dans le contexte de ces méthodes l'ensemble des diagnostics de faisceau installés sur SPIRAL. Une attention particulière est portée à la conception et au test d'un capteur, basé sur un scintillateur plastique, permettant de mesurer la phase d'un faisceau d'ions de faible intensité en cours d'accélération dans le cyclotron.

During the last decade, the need of high ion beam intensities urged the cyclotron laboratories to amplify the efforts to study the space charge effects in these machines. The cyclotron space charge effects are intimately linked to two specific features of this kind of accelerator; - the beam is formed of a succession of bunches having about the same size for transverse and longitudinal dimensions, - the radial and longitudinal motions are strongly coupled. The analytical model developed in this thesis explains some effects produced by the space charge forces. It describes the motion of an ion contained in a bunch. This ion moves under the effects of the guiding field forces, the accelerator cyclotron field forces and the space charge forces created by the other particles of the bunch. The solutions of the first order differential equations describe the small motion around one particle, which is taken as a reference particle. These solutions are valid in the vicinity of the bunch center, where the space charge forces are considered linear. The results of the model are compared with those obtained from a multiparticle code. This code has been already used successfully at GANIL (the Great National Heavy Ions Accelerator). The evolution of the whole beam has also been studied with this code, which takes into acount the non linear space charge effects and all the couplings. The results obtained by the numerical study of a proposed new injector for the cyclotrons of GANIL shows that it is possible to obtain an important increase of the beam intensity, Depuis une dizaine d’années, le désir d'obtenir des faisceaux d'ions intenses a partir de cyclotrons a conduit a amplifier les efforts concernant l’étude des effets de la charge d'espace dans ces machines. Les effets de la charge d'espace dans un cyclotron sont intimement lies a deux caractéristiques spécifiques de ce type d'accélérateur: - le faisceau est constitue d'une suite de paquets dont les dimensions transversales et longitudinales sont du même ordre, - les mouvements radial et longitudinal sont fortement couples. Le modèle présenté dans cette thèse permet d'expliquer certains des effets produits par la charge d'espace. Il décrit le mouvement d'un ion appartenant a un paquet et soumis aux forces du champ de guidage, du champ accélérateur du cyclotron et du champ de charge d'espace crée par les autres particules du paquet. Les solutions des équations différentielles développées au premier ordre décrivent les petits mouvements des ions autour d'une particule de référence et sont valables au voisinage du centre du paquet, la ou les forces de charge d'espace sont considérées comme étant linéaires. Les résultats donnes par ce modèle sont compares a ceux obtenus a partir d'un programme de simulation déjà utilise avec succès lors de l’étude des cyclotrons a secteurs séparés du Grand Accélérateur National d'Ions Lourds: l'accord est excellent. L’évolution de l'ensemble du faisceau est aussi étudiée avec ce programme qui tient compte des effets non linéaires des forces de charge d'espace et de tous les couplages. Les résultats obtenus lors de l’étude numérique d'un nouvel injecteur pour les cyclotrons du Grand Accélérateur National d'Ions Lourds montrent qu'il serait possible d'obtenir une très forte augmentation de l’intensité des faisceaux

The aim of the OAE and OAI projects developed at GANIL is respectively to increase the ''medium'' heavy ion energies to get 45 MeV/A beams up to Xenon, and to increase the beam intensities. This study deals with the injection stage of the second of these operations. In this new design, the ECR source potential is 100 kV to avoid losses due to space charge. The inflector used for the injection in the cyclotron NC01 is a spiral type with two parameters. The equations of motion are straighforward to obtain and numerical simulation programs have been developed. It is then possible to compute the transfer matrix of this inflector and to study the behavior of the beam inside it. It is necessary to introduce an electrostatic quadrupole after the inflector exit to realize a good matching to the cyclotron with the condition of always staying inside the inflector acceptance. For these matching conditions, the inflector transmission is increased if one introduces a rotation of the inflector exit face. It is then possible to transfer beams with the required emittances and intensities in the OAI project. The knowledge of the inflector characteristics makes it possible to design an axial injection line to obtain a matched beam, Le but des opérations OAE et OAI développées au GANIL est respectivement d'augmenter l’énergie des ions lourds de façon a délivrer des faisceaux de 45 MeV/A jusqu'au Xenon et d'en améliorer les intensités. Le travail retrace ici porte sur l’étage injecteur de la seconde de ces opérations. Dans cette configuration, une source ECR est portée a un potentiel de 100 kV afin d’éviter les pertes dues a la charge d'espace. L'inflecteur retenu pour réaliser l'injection dans le cyclotron NC01 est de type spiral a deux paramètres. Devant la difficulté de déterminer analytiquement les équations du mouvement, des programmes de simulation numérique ont été développés. Ces derniers permettent de calculer la matrice de transfert de cet inflecteur et d’étudier le comportement du faisceau a sa traversée. L'introduction d'un quadrupôle électrostatique en aval de l'inflecteur est nécessaire pour réaliser une bonne adaptation dans le cyclotron tout en restant dans l'acceptance de l'inflecteur. Pour les conditions d'adaptation retenues, la transmission de l'inflecteur est améliorée par l'introduction d'une rotation de sa face de sortie. Il est alors possible d'y transférer des faisceaux dont les émittances et les intensités sont celles envisagées dans le projet OAI. Connaissant les caractéristiques de l'inflecteur, la structure de la ligne d'injection axiale a pu être determinée afin de fournir un faisceau adapte

A Moak type radio frequency ion source, capable of producing a pulsed beam of deuterons has been built for use with a Cockcroft-Walton accelerator. Pulsed deuterons striking a deuteron target produce neutrons in bursts thus allowing dynamic measurements of moderator and reactor core properties. Beam pulsing is accomplished by means of an einzel lens and an alternating potential applied to a pair of deflection plates. Proteins have been used exclusively in adjusting the source for optimum results since the radiation background due to the protons is much less than that due to deuterons. In actual experiments, however, when using deuterons, no modifications need to be made in the source. Beam currents have been measured at the source and at a target located at the end of the accelerator tube. Maximum currents measured are 150 microamperes and 60 microamperes respectively. Details of construction, maximum operating conditions, and oscillogram sof purse shapes are included in this report. M.S.

Since last RuPAC two runs of the Nuclotron operation were performed. The run #54 performed in February ' March of 2017 was dedicated to polarized beam acceleration. One of the achievements was the acceleration of polarized proton beam performed at the Nuclotron for the first time. During the run #55 in February- April of 2018 the Nuclotron provided heavy ion beams for first fixed target experiments in the frame of the NICA scientific program. These and other results of the facility operation and development are presented., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia

The research of the processes occurring during interaction of heavy ions with plasma is carried out on the Heavy Ion RFQ HIP-1 (heavy Ion Prototype) in the ITEP. The HIPr-1 is a heavy ion RFQ linac which accelerates ion beams generated by either MEVVA ion source or duoplasmatron. It provides accelerated beam of ions from C+ to U4+ with energy of 101keV/n and several mA of current. Gas-discharge plasma target which was produced in ITEP is used for the measurement of ion energy losses in the ionized matter. The diaphragms at the entrance and exit of the plasma target provide the necessary pressure into the transport channel (which is 10⁻⁶ mbar), while the gas pressure in the target equals to several mbar. The design of the beam transport channel for performing experiments to determine the energy losses in plasma was developed based on the beam dynamics simulation. According to the obtained results the first successful tests on the HIPr-1 were held., Proceedings of the 26th Russian Particle Accelerator Conf., RUPAC2018, Protvino, Russia