Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under creating of FLNR JINR Irradiation Facility based on the cyclotron U400R. The main systems of U400R are based on the U400 cyclotron. The objectives of this project are: - to increase the intensity of accelerated 48Ca ion beams from 1.2 puA to 2 puA; - to expand the energy range of accelerated ions from 2–20 MeV per unit mass to 0.8–25 MeV per unit mass; - to extract ion using stripping foil and deflector; - to reduce the energy spread in the beam to 3×10⁻³. The results of calculating the parameters of the new RF-system are given in this work.

The Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research continues work on the reconstruction of the U400 cyclotron into a new U400R accelerator complex designed to produce accelerated ion beams with an atomic mass in the range of A = 4 ÷ 209 and an energy of 0.8 ÷ 25 MeV/nucleon. The intensity of accelerated ions will be about 2.5 μA particles for 48Ca ions. The axial injection system of the U400R cyclotron is a modernization of a similar system of the U400 cyclotron. The report presents the results of calculating the axial injection beam line of the cyclotron.

U400M isochronous cyclotron was create on the base of U300 classic cyclotron and is under operation at FLNR, JINR since 1996. U400M cyclotron is intended for accelerating the ion beams with A/Z= 2.286 – 9 to energy W = 80 – 6 MeV/nucl. Cyclotron have H-type main magnet with 4-meter pole diameter and 4 pairs of spiral type sectors. In 2022 year, the reconstruction of cyclotron magnetic structure was held on. The reconstruction included the replacement of magnet main coil, mapping and correction of cyclotron magnetic field. In the frame of the mapping, the magnetic field was corrected to improve its average radial distribution and to compensate the first harmonic. For cyclo- tron magnetic field mapping the automatic measurement system, based on 14 Hall probes, was used.

At the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research (JINR), work is continuing on a new multipurpose applied science facility based on the DC-140 cyclotron. The intensity of the accelerated ions will be about 1 pμA for light ions (A < 86) and about 0.1 pμA for heavier ions (A > 132). The beam transport system consists of three lines: for the SEE testing of microchips, for the production of track membranes, and for solving applied physics problems. The beam focusing in the beam lines is provided by a set of quadrupole lenses with gradients reaching 6 T/m.

— The new heavy-ion isochronous cyclotron DC140 is being built at the Joint Institute for Nuclear Research. The DC140 facility is intended for the SEE testing of microchips, the production of track membranes, and for solving applied physics problems. The cyclotron will produce accelerated beams of ions A/Z = 5–5.5 and 7.5–8.25 with a fixed beam energy of 4.8 and 2.124 MeV/n, respectively. The passive magnetic channel is part of the beam extraction system and is used to produce radial focusing of the extracted beam after its deflection. Placed in the fringe magnetic field, the channel transforms it to produce a radially growing gradient along the beam path near the sector edge. In this work, the results of trajectory analysis, 2D and 3D simulations, and design details of the passive magnetic channel are presented.

The Flerov Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research is continuing works on a new multipurpose applied science facility based on the DC140 cyclotron. The axial injection systems of DC140 cyclotron are a reconstruction of the DC72 cyclotron ones. The overview of the elements of the axial injection system is presented in this report.

An optimized magnetic specification has been searched for a PM quadrupole constructed for the DC-140 cyclotron in JINR, Dubna. The field inhomogeneity should be reduced to come closer to an ideal distribution. The quad parameters should be determined with very high mechanical and magnetic precision in order to reach the specified gradient. Results of the analytic study based on a 2D model gave initial values for the PM blocks dimensions and orientations. To ensure stringent performance criteria, parametrized 2D and 3D models of the quad were built. These models were used to optimize the magnet configuration, analyze its sensitivity to various errors and derive parameter tolerances. Additional adjustment to suitable field quality is foreseen using results of a trajectory analysis and acceptance inspection. The design parameters for the best suited magnet configuration are presented and the performance criteria are defined. However, an electromagnetic analysis of the selected configuration has revealed that the relative field error adopted previously as the optimization criterion gives low accuracy estimate. Alternative estimations are proposed utilizing the field gradient error as the basic criterion to satisfy the constraint on the field inhomogeneity.

Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under creating of FLNR JINR Irradiation Facility based on the cyclotron DC140. The facility is intended for SEE testing of microchip, for production of track membranes and for solving of applied physics problems. The main systems of DC140 are based on the DC72 cyclotron ones that now are under reconstruction. 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 pμA for light ions (A≤86) and about 0.1 pμA for heavier ions (A≥132). The injection into cyclotron will be realized from the external room temperature 18 GHz ECR ion source. The design and simulation of the axial injection system of the DC140 cyclotron is presented in this report. INTRODUCTION Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research continues the works under the creating of Irradiation Facility based on the DC140 cyclotron [1]. The DC140 will be a reconstruction of the DC72 cyclotron [2, 3]. Table 1 presents the main parameters of DC140 cyclotron. Table 1: Main Parameters of DC140 Cyclotron Pole (Extraction) Radius, m 1.3 (1.18) Magnetic field, T 1.415÷1.546 Number of sectors 4 RF frequency, MHz 8.632 Harmonic number 2 3 Energy, MeV/u 4.8 2.124 A/Z range 5.0÷5.5 7.57÷8.25 RF voltage, kV 60 Number of Dees 2 Ion extraction method electrostatic deflector Deflector voltage, kV 73.5 The irradiation facility will be used for Single Event Effect (SEE) testing of microchips by means of ion beams (16O, 20Ne, 40Ar, 56Fe, 84,86Kr, 132Xe, 197Au and 209Bi) with energy of 4.8 MeV per unit mass and having mass-tocharge ratio A/Z in the range from 5.0 to 5.5. Besides the research works on radiation physics, radiation resistance of materials and the production of track membranes will be carrying out by using the ion beams with energy of about 2.124 MeV per unit mass and A/Z ratio in the range from 7.577 to 8.25. The working diagram of DC140 cyclotron is shown in Fig. 1. The acceleration of ion beam in the cyclotron will be performed at constant frequency f = 8.632 MHz of the RF-accelerating system for two different harmonic numbers h. The harmonic number h = 2 corresponds to the ion beam energy W = 4.8 MeV/u and value h = 3 corresponds to W = 2.124 MeV/u. The intensity of the accelerated ions will be about 1 pμA for light ions (A≤86) and about 0.1 pμA for heavier ions (A≥132). Figure 1: Working diagram of DC140 cyclotron. The axial injection system of DC140 cyclotron will be adapted from the existing DC72 cyclotron one [4]. This report presents the design and simulation of the beam dynamic in the axial injection beam line of DC140 cyclotron. The simulation was carried out by means of MCIB04 program code [5]. ECR ION SOURCE The ion beams are produced in room temperature ECR ion source DECRIS-5 designed in Flerov Lab of JINR [6]. The working frequency DECRIS-5 is equal to 18 GHz. It is able to produce the beams of ion from 22Ne to 209Bi. The parameters of the ion beams at the extraction hole of ECR ion source are contained in Table 2. ___________________________________________ † nyk@jinr.ru 12th Int. Particle Acc. Conf. IPAC2021, Campinas, SP, Brazil JACoW Publishing ISBN: 978-3-95450-214-1 ISSN: 2673-5490 doi:10.18429/JACoW-IPAC2021-TUPAB191 TUPAB191 C on te nt fr om th is w or k m ay be us ed un de rt he te rm s of th e C C B Y 3. 0 lic en ce (© 20 21 ). A ny di st ri bu tio n of th is w or k m us tm ai nt ai n at tr ib ut io n to th e au th or (s ), tit le of th e w or k, pu bl is he r, an d D O I 1852 MC4: Hadron Accelerators A13 Cyclotrons Table 2: Parameters of Ion Beam Used in Simulation Ions/harmonic number 209Bi38+/2 197Au26+/3 A/Z 5.5 7.58 Extraction voltage Uinj, kV 18.86 11.55 Beam current, μА 1.25 6 Beam diameter, mm 8 Emittance,  mm  mrad 220 237 BEAM LINE SCHEME The scheme of the beam line is shown in Fig. 2. Figure 2: Scheme of the axial injection beam line. The length of the beam line is equal to 5.065 m. The 90degree analyzing magnet M90 separates the injected beam. The solenoidal lenses S1-4 focus and match beam with the acceptance of the spiral inflector I for all level of the cyclotron magnetic field. The two-harmonic buncher BN increases the beam capture into acceleration. Two movable diaphragms CL1, 2 are used for analysis of the beam spectra. ANALYZING MAGNET M90 The analyzing magnet M90 has a bending radius RM equal to 0.4 m, gap 80 mm and maximum magnetic field 0.2 T. SOLENOIDS S1-4 The solenoids S1-4 are the part of existing DC72 cyclotron axial injection beam line [4]. Its on-axis magnetic fields are shown in Fig. 3. Figure 3: On-axis magnetic field of solenoids. MAGNETIC PLUG The channel apertures in the magnetic plug P are shown in Fig. 4. Figure 4: Magnetic plug scheme. TWO-HARMONIC BUNCHER BN To improve the efficiency of beam capture into the acceleration the two-harmonic buncher BN, located outside the yoke of the magnet at a distance of 2.341 m from the median plane of the cyclotron, is used. The maximum applied voltage at the grids of buncher is 500 V for the injecting ions having A/Z = 5.5 (209Bi38+). The efficiency of bunching is approximately equal to 2.75 (see Fig. 5). Figure 5: Bunching efficiency. SPIRAL INFLECTOR I To simplify the operation of the cyclotron only one inflector with a magnetic radius of 30 mm is used. In the case of accelerating with harmonic number of h = 2, the injection voltage Uinj changes from 17.15 kV to 18.86 kV for the injected ions with A/Z in the range from 5.0 (40Ar8+) to 5.5 (209Bi38 +). In the case of h = 3, the voltage Uinj changes from 11.55 kV to 12.58 kV for the injected ions with A/Z in the range from 7.577 (197Au26+) to 8.25 (132Xe16+). SIMULATION RESULTS The calculations of ion injection with the parameters specified in Table 2 were carried out. In all cases, the transfer efficiency is equal to 100%. A/Z=5.5, B0=1.546 T, ρM=30.0 mm, h=2 Transport of 209Bi38+ ion beam was considered. In this case the magnetic field at the center of the cyclotron B0 = 1.546 T is maximal. The horizontal (H) and vertical -45-40-35-30-25-20-15-10 -5 0 5 10 15 20 25 30 35 40 45 см 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5

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 – axial injection, main magnet, RFand 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 (A≤86) 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. INTRODUCTION Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under the creating of Irradiation Facility based on the DC140 cyclotron [1]. The DC140 will be a reconstruction of the DC72 cyclotron [2, 3]. Table 1 presents the main parameters of DC140 cyclotron. Table 1: Main Parameters of DC140 Cyclotron Pole (Extraction) Radius, m 1.3 (1.18) Magnetic field, T 1.415÷1.546 Number of sectors 4 RF frequency, MHz 8.632 Harmonic number 2 3 Energy, MeV/u 4.8 2.124 A/Z range 5.0÷5.5 7.57÷8.25 RF voltage, kV 60 Number of Dees 2 Ion extraction method electrostatic deflector Deflector voltage, kV 73.5 The irradiation facility will be used for Single Event Effect (SEE) testing of microchips by means of ion beams (16O, 20Ne, 40Ar, 56Fe, 84,86Kr, 132Xe, 197Au and 209Bi) with energy of 4.8 MeV per unit mass and having mass-tocharge ratio A/Z in the range from 5.0 to 5.5. Besides the research works on radiation physics, radiation resistance of materials and the production of track membranes will be carrying out by using the ion beams with energy of about 2.124 MeV per unit mass and A/Z ratio in the range from 7.577 to 8.25. The working diagram of DC140 cyclotron is shown in Fig. 1. The acceleration of ion beam in the cyclotron will be performed at constant frequency f = 8.632 MHz of the RF-accelerating system for two different harmonic numbers h. The harmonic number h = 2 corresponds to the maximal and value h = 3 – to minimal ion beam energy. The intensity of the accelerated ions will be 1 pμA for light ions (A≤86) and 0.1 pμA for heavier ions (A≥132). Figure 1: Working diagram of DC140 cyclotron. The axial injection system of DC140 cyclotron will be adapted from the existing DC72 cyclotron one [4]. This report presents the design and simulation of the beam dynamic in the axial injection beam line of DC140 cyclotron. The simulation was carried out by means of MCIB04 program code [5]. ECR ION SOURCE The ion beams are produced in room temperature ECR ion source DECRIS-5 designed in Flerov Lab of JINR [6]. The working frequency DECRIS-5 is equal to 18 GHz. It is able to produce the beams of ion from 22Ne to 209Bi. BEAM LINE ELEMENTS The scheme of the beam line is shown in Fig. 2. The length of the beam line is equal to 5.065 m. The 90-degree analyzing magnet M90 separates the injected beam. The solenoidal lenses S1-4 focus and match beam with the acceptance of the spiral inflector I for all level of the cyclotron magnetic field. Two movable diaphragms CL1, 2 are † nyk@jinr.ru 27th Russian Particle Acc. Conf. RuPAC2021, Alushta, Russia JACoW Publishing ISBN: 978-3-95450-240-0 ISSN: 2673-5539 doi:10.18429/JACoW-RuPAC2021-MOPSA50 Heavy ion accelerators MOPSA50 209 C on te nt fr om th is w or k m ay be us ed un de rt he te rm s of th e C C B Y 3. 0 lic en ce (© 20 21 ). A ny di st ri bu tio n of th is w or k m us tm ai nt ai n at tr ib ut io n to th e au th or (s ), tit le of th e w or k, pu bl is he r, an d D O I

Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under creating of FLNR JINR Irradiation Facility based on the cyclotron DC140. The facility is intended for SEE testing of microchip, for production of track membranes and for solving of applied physics problems. The DC140 cyclotron is intended for acceleration of heavy ions with mass-tocharge 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 (A<86) and about 0.1 pmcA for heavier ions (A>132). The system based on three main elements electrostatic deflector, focusing magnetic channel, Permanent Magnet Quadrupole lens is used in the DC140 cyclotron for extraction of the accelerated beam. The design and simulation of the beam extraction system from the DC140 cyclotron are presented in this report. INTRODUCTION The DC140 is a sector cyclotron is intended for acceleration of heavy ions with variation of the magnetic field level at range Bo=1.415÷1.546 T [1]. The main parameters of DC140 cyclotron are given in Table 1. The DC140 will be a reconstruction of the DC72 cyclotron [2, 3]. In DC72 beam was extracted by stripping method. In DC140 the extraction will be carried out using an electrostatic deflector. Table 1: DC140 Cyclotron Main Parameters Parameter Value Pole (extraction) radius [m] 1.3(1.18) Number of sectors 4 RF frequency [MHz] 8.632 Harmonic number 2 3 Energy [MeV/u] 4.8 2.124 A/Z range 5.0÷5.5 7.57÷8.25 RF voltage [kV] 60 Number of Dees 2 Ion extraction method electrostatic deflector Deflector voltage [kV] 73.5 For beams extraction from the cyclotron is used the electrostatic deflector. The extraction system of the DC140 cyclotron consist a next elements (see Fig. 1): 1. Electrostatic deflector (ESD); 2. Focusing magnetic channel (MC); 3. Permanent Magnet Quadrupole lens (PMQ). Figure 1: Layout of the elements of extraction system OPTIMIZATION OF THE CURVATURE RADIUS OF THE ELECTROSTATIC DEFLECTOR Azimuthal position of the electrostatic deflector 70÷110 degrees (40 degrees). The main parameters of the electrostatic deflector are given in Table 2. Table 2: Parameters of the Electrostatic Deflector Parameter Value Azimuthal position [deg] 70÷110 Max. Voltage [kV] 73.5 Thickness of the “septum” plate [mm] 0.3÷1.0 Gap between plates [mm] 9 Displace of the deflector edges [mm] ± 10 The task of the optimization comes down to minimizing the sum of differences of radius of curvature of the deflector Rd centered at a point (X0; Y0) and distances from this point to the point of the extraction orbit as shown in Eq. (1).

The design and specification choices are described for a PM quadrupole used to enable beam transport in a cyclotron. First an analytic study with a simplified 2D model is performed to give initial values for magnet configuration and performance. Characteristics of PM blocks and cylinders are analysed. Then a 3D parametrized model is used to solve the direct magnetostatic problem and accurately define quad specifications. Simulations are carried out with KOMPOT electromagnetic code utilizing the differential formulation. The regulariza- tion method is applied to solve the inverse problem. Magnetic characteristics, dimensions and shapes of the PM units and iron parts are determined in order to reach the specified field gradient. Possible correction of the resulting the ideal specification is discussed with respect to additional constraints put by practical implementation. Candidate PM materials are proposed. Simulated field maps are presented. The method described may serve as a basis for virtual prototyping and be integrated into end-to-end design and construction of magnet systems.

Abstract 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 8.632MHz. In this report, the results of design and simulation of the beam acceleration and extraction are presented.

The DC280 is the high current cyclotron with design beam intensities up to 10 pμA for ions with energy from 4 to 8 MeV/nucleon. It was developed and created at the FLNR JINR. The accelerator has worked 9350 hours. Experiments on acceleration of 12C, 40Ar, 48Ca, 48Ti, 52Cr and 84Kr beams production were carried out. The following intensities of accelerated beam have been achieved: 10 pμA for 12C+2; 10.4 pμA for 40Ar+7; 7.1 pμA for 48Ca+10, 1 pμA for 48Ti+10; 2.4 pμA for 52Cr+10; 1.43 pμA for 84Kr+14. The total acceleration efficiency from ion source to transport channel was about 50%. DC-280 DESCRIPTION DC-280 is the accelerated ions source for experiments on synthesis of super heavy elements [1]. It is part of Super Heavy Element (SHE) Factory which was created in FLNR in JINR. It is isochronous cyclotron designed for acceleration of ion with mass to charge ratio from 4.5 to 8 to energy from 4 to 8 MeV/n. Main parameters design and achieved present in Table 1. Table 1: Main Parameters of DC-280 Cyclotron Electron Cyclotron Resonance (ECR) source DECRIS-PM is used for production of ions [2, 3]. It has magnetic structure from permanent magnets. It placed on high voltage platform with work voltage up 70 kV for increasing efficiency of initial beam transport and capture to acceleration [4]. For injection to cyclotron, one of two spiral inflectors with magnetic radius Rm= 7.5 (type A) or 9.2 (type B) is used. During experiments both of them were successful tested. There is electrostatic quadrupole lens in central part of cyclotron. Polyharmonic buncher is used for increasing of ions capture to acceleration [4]. Accelerated beam is extracted from cyclotron by electrostatic deflector. It works in conjunction with magnetic channel. Deflector length is 1.3 m. The work electric field strength in gap between electrodes is up 90 kV/cm [1]. Extracted beam is delivered by transport to experimental setups [5]. There are 5 channels connected with 3 isolated halls. On 26 December 2018, the first accelerated beam was got inside of DC-280 cyclotron [1, 6]. On January 2019, accelerated beam was extracted from cyclotron to transport channel. On September, the new experimental facility Dubna Gas Filled Separator 2 was mounted, and test with accelerator beam was started [7]. On December of 2019, work with beam of 48Ca was initiated. On November 2020, the first experiment on production of 115Mc was started. The cyclotron has worked 9350 hours during three years. Different mode of work with different ions and energy were explored. The work diagram of DC-280 cyclotron with marks of tested regimes is presented on Fig. 1. The cyclotron has shown reliable and highly effective work. The control and extraction systems were optimized for improving of efficiency and reliable of accelerator. Figure 1: DC-280 work diagram with mark of test modes.

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 pμA for light ions (A<86) and about 0.1 pμA 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.

Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under creating FLNR JINR Irradiation Facility based on the cyclotron DC140. The facility is intended for SEE testing of microchip, for production of track membranes and for solving of applied physics problems. The main systems of DC140 are based on the DC72 cyclotron ones that now are under reconstruction. The DC140 cyclotron is intended for acceleration of heavy ions with mass-to-charge ratio A/Z within interval from 5 to 5.5 up to two fixed energies 2.136 and 4.8 MeV per unit mass. The intensity of the accelerated ions will be about 1 pμA for light ions (A<86) and about 0.1 pμA for heavier ions (A>132). The beam extraction system consists of electrostatic deflector and two magnetic channels. The simulation of the extraction system of the cyclotron is presented in this report. The extracted beams characteristics outside the cyclotron, that will serve as initial conditions for the design of experimental beam lines of FLNR JINR IF are determined. INTRODUCTION Flerov Laboratory of Nuclear Reaction of Joint Institute for Nuclear Research carries out the works under the creating of Irradiation Facility based on the DC140 cyclotron. The DC140 will be a reconstruction of the DC72 cyclotron [1, 2]. Table 1 presents the main parameters of DC140 cyclotron. Table 1: DC140 Cyclotron Main Parameters Parameter Value Pole (extraction) radius, m 1.3 (1.18) Magnetic field, T 1.415 1.546 Number of sectors 4 RF frequency, MHz 8.632 Harmonic number 2 3 Energy, MeV/u 4.8 2.124 A/Z range 5.0 5.5 7.577 8.25 RF voltage, kV 60 Number of Dees 2 Ion extraction method electrostatic deflector Deflector voltage, kV 70 The irradiation facility will be used for Single Event Effect (SEE) testing of microchips by means of ion beams (16O, 20Ne, 40Ar, 56Fe, 84,86Kr, 132Xe, 197Au and 209Bi) with energy of 4.8 MeV per unit mass and having mass-tocharge ratio A/Z in the range from 5.0 to 5.5. Besides the research works on radiation physics, radiation resistance of materials and the production of track membranes will be carrying out by using the ion beams with energy of about 2.124 MeV per unit mass and A/Z ratio in the range from 7.577 to 8.25. The working diagram of DC140 cyclotron is presented in report MOP019 at this conference [3]. The acceleration of ion beam in the cyclotron will be performed at constant frequency f = 8.632 MHz of the RF-accelerating system for two different harmonic numbers h. The harmonic number h = 2 corresponds to the ion beam energy W = 4.8 MeV/u and value h = 3 corresponds to W = 2.124 MeV/u. The intensity of the accelerated ions will be about 1 pμA for light ions (A  86) and about 0.1 pμA for heavier ions (A 132). The extraction system of DC140 cyclotron differs from DC72 cyclotron one, based on extraction by stripping foil [4], and consists of electrostatic deflector and two magnetic channels. The first is the passive channel placed in the region of strong magnetic field of the cyclotron. The second is permanent magnet channel placed in the region of low level magnetic field. This report presents the simulation of the 209Bi38+ ion beam dynamic in the extraction beam line of DC140 cyclotron. CYCLOTRON MAGNETIC FIELD The magnetic field of DC140 cyclotron within the project range is formed by variation of the currents in the main and in ten correcting coils. Radial distribution of the magnetic fields for acceleration of 209Bi38+ ions up to energy W = 4.8 MeV/u is shown in Fig. 1 [5]. Figure 1: Magnetic fields for acceleration of 209Bi38+ ions. Breal – magnetic field formed by main coils ; Biso – isocronous magnetic field ; Bform – magnetic field formed by main and correcting coils. For the other kind of ions, the form of magnetic field is similar to the considering case. ___________________________________________ † nyk@jinr.ru 22nd Int. Conf. on Cyclotrons and their Applications Cyclotrons2019, Cape Town, South Africa JACoW Publishing ISBN: 978-3-95450-205-9 doi:10.18429/JACoW-Cyclotrons2019-MOP020 02 Cyclotron Technology MOP020 73 Co nt en tf ro m th is w or k m ay be us ed un de rt he te rm so ft he CC BY 3. 0 lic en ce (© 20 19 ). A ny di str ib ut io n of th is w or k m us tm ai nt ai n at tri bu tio n to th e au th or (s ), tit le of th e w or k, pu bl ish er ,a nd D O I

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.