The NICA (Nuclotron-based Ion Collider fAcility) accelerator complex consists of a collider and an injection complex. The injection complex of heavy ions includes ion source, linear accelerator, a 25 T m SC Booster synchrotron, a 38 T m SC synchrotron Nuclotron, and beam transfer lines. One of the main tasks in complex commissioning and tuning are the measurement and correction of the beam closed orbit. The software, written for orbit correction, was successfully tested during the commissioning runs. The paper describes the software and hardware developments for orbit measurement and correction.

One of the key facilities in the chain of heavy ion injection of the NICA Collider is a new 25 T m superconducting booster synchrotron (Booster). Since commissioning of the facility in December 2020, four runs with beams of various ions have been carried out, two of which were accompanied by experiments at the BM@N facility. The first results of studying the magneto-optic characteristics of the Booster and measuring beam parameters using the correction system of the leading magnetic field are presented. The prospects of such studies in experiments and research on tuning the injection complex and the NICA Collider are also discussed.

The NICA accelerator complex intended for studying baryonic matter and research in spin physics is currently at the stage of construction and mounting at the JINR. The NICA injection complex was designed to produce heavy ions with an energy of 1–3.9 GeV/u. The injection complex consists of two new accelerators: Heavy Ion Linear Accelerator, HILAC, and the superconducting synchrotron, Booster, and the modernized superconducting synchrotron, Nuclotron. The injection facility provides heavy ion beams for the NICA collider and the fix target experiments. The results of the fourth Booster-Nuclotron beam run for fix target experiments on the BM@N setup are discussed. The completion of the facility equipment construction and mounting are also presented along with the plans of first collider runs.

In this work we present the test run results for the electron cooling system at the Booster synchrotron, which were conducted at the Nuclotron-based Ion Collider facility (NICA) injection complex in 2020–2023. We have demonstrated a successful cooling of the 56Fe14+ and 124Xe28+ ion beams at the injection energy 3.2 MeV/u. In this work, we provide parameters of the ion and electron beams, as well as a detailed description of the tuning procedures used for the e-cooling system during the experiments.

The injection chain of the NICA Collider (JINR, Dubna) consists of various ion sources, two linear accelerators, a 25 T m superconducting (SC) Booster synchrotron, the existing SC synchrotron Nuclotron, and beam transfer lines. Construction of the Booster synchrotron was finished in 2020 and the first machine Run with ion beam was successfully carried out in December. So far, three commissioning Runs with various ion beams have been successfully completed. The tuning processes, the study of the beam parameters, and optical characteristics of the Booster during these Runs are presented.

The distribution coefficients of Hf(IV) and Lu(III) between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and mixed HCl–H 2 C 2 O 4 solutions and between Dowex 50W×8 cation exchanger or Dowex 1×8 anion exchanger and citric acid solutions were determined. A number of modifications of the 172 Hf → 172 Lu generator, based on reverse separation schemes, were examined. Systems consisting of an anion-exchange resin and a solution of appropriate organic acid were taken as a chemical basis of the generator. Irreversible sorption of 172 Lu in generator columns was studied. The optimum operation mode of the 172 Hf → 172 Lu generator based on the reverse-tandem scheme with periodic transfer of the parent radionuclide into the liquid phase was determined.

This paper presents the design of the DECRIS-PM ECR ion source developed for the DC-280 cyclotron under construction at FLNR JINR. The results of the ion-source testing are presented. Highintensity beams for gaseous (900 μA of Ar8+, 550 μA of Ar9+, 160 μA of Kr15+, etc.) and solid targets (450 μA of Mg5+, 220 μA of Ca9+, 90 μA of Ti9+, etc.) are produced during the testing.

ABSTRACT The distribution of some rare-earth elements (REEs) on Uranium and TEtraValent Actinides (UTEVA) resin was determined from different concentrations of inorganic (HCl, HNO3, HClO4, HPF6) and one organic acid – CCl3COOH. Low sorption of all REEs in the range of 1 M–5 M HNO3 was observed. In more concentrated HNO3, a rapid increase of the distribution coefficients (Kd) was noticed with an increase in the atomic number of the lanthanides as well as in Y and Sc. The system UTEVA–CCl3COOH showed a higher selectivity for Eu(III). Chromatographic elution profiles were checked in order to confirm the obtained Kd values.

The production of metal ion beams by electron cyclotron resonance (ECR) ion sources using the MIVOC (Metal Ions from Volatile Compounds) method is described. The method is based on the use of metal compounds which have high vapor pressure at room temperature, e.g., C2B10H12, Fe(C5H5)2, etc. Intense ion beams of B and Fe were produced using this method at the FLNR JINR cyclotrons. Experiments on the production of cobalt, chromium, vanadium, germanium, and hafnium ion beams were performed at the test bench of ECR ion sources. Main efforts were put into production and acceleration of 50Ti ion beams at the U-400 cyclotron. The experiments on the production of 50Ti ion beams were performed at the test bench using natural and enriched compounds of titanium (CH3)5C5Ti(CH3)3. In these experiments, 80 μA 48Ti5+ and 70 μA 48Ti11+ beam currents were obtained at different settings of the source. Following successful tests, two 3-week runs were performed with 50Ti beams at the U-400 cyclotron aimed to perform experiments on the spectroscopy of superheavy elements. The intensity of the injected 50Ti5+ beam was 50–60 μA. The source worked stably during experiments. The compound consumption rate was determined at about 2.4 mg/h, which corresponded to the 50Ti consumption of 0.6 mg/h.

Abstract Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is 90Nb. It has a half-life of 14.6 h that allows visualizing and quantifying biological processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or drug delivery systems and nanoparticles. 90Nb exhibits a positron branching of 53% and an average kinetic energy of emitted positrons of E mean =0.35 MeV. Currently, radionuclide production routes and Nb V labeling techniques are explored to turn this radionuclide into a useful imaging probe. However, efficient separation of 90Nb from irradiated targets remains in challenge. Ion exchange based separation of 90Nb from zirconium targets was investigated in systems AG 1 × 8 – HCl/H2O2 and UTEVA-HCl. 95Nb (t 1/2 = 35.0 d), 95Zr (t 1/2 = 64.0 d) and 92m Nb (t 1/2 = 10.15 d) were chosen for studies on distribution coefficients. Separation after AG 1 × 8 anion exchange yields 99% of 90/95Nb. Subsequent use of a solid-phase extraction step on UTEVA resin further decontaminates 90/95Nb from traces of zirconium with yields 95% of 90/95Nb. A semi-automated separation takes one hour to obtain an overall recovery of 90/95Nb of 90%. The amount of Zr was reduced by factor of 108. The selected separation provides rapid preparation (< 1 h) of high purity 90Nb appropriate for the synthesis of 90Nb-radiopharmaceuticals, relevant for purposes of immuno-PET. Applying the radioniobium obtained, 90/95Nb-labeling of a monoclonal antibody (rituximab) modified with desferrioxamine achieved labeling yields of >90% after 1 h incubation at room temperature.

Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is 90 Nb. It has a half-life of 14.6 h that allows visualizing

Summary A technique of selenium purification from 232Th, 238U, 226,228Ra, 227Ac and 40K was developed. This technique is simple to perform and employs a minimum number of highly pure reagents (bidistilled water, nitric acid). Operations carried out during purification (elution, evaporation) practically exclude losses of the target product (chemical yields of Se > 99%). A test purification of 100 g of selenium was carried out using this technique. The efficiency of this technique was confirmed by low background gamma spectrometry of the purified selenium sample. Distribution coefficients of Th, U, Ra and Ac on DOWEX 50W-×8 cation-exchange resin at different concentrations of selenium and nitric acid were experimentally determinated. Instrumental neutron activation analysis of bidistilled water, deionized water and nitric acid was performed.

Procedures were developed for isolation and separation of radionuclides from a thorium target irradiated with 300-MeV protons. A large set of radionuclides, including those of heavy elements (225,226Ac, 223,224,225Ra, 230U, 230Pa), were obtained. A perspective scheme was suggested for separation of radionuclides from irradiated thorium.

1099 Objectives 90Nb is a potential PET nuclide (T1/2 = 14.6 h and high positron branching 53%). Promising results in labeling and in vitro evaluation of 90Nb-labeled monoclonal antibodies confirm expectation about 90Nb as an appropriate isotope for immuno-PET. In recent work, direct flow separation strategy to isolate 90Nb from Zr or Mo irradiated targets was developed. Methods Natural Zr and Mo targets were irradiated at Phasotron facilities at Joint Institute for Nuclear Research (JINR), Dubna, Russian Federation. Two targets were irradiated simultaneously at intern beam at energy 100 MeV, current 4 µA for 30 minutes. Distribution coefficients for ZrIV and NbV in mixture oxalic and hydrochloric acid were measured. Finally, anion exchange chromatography in hydrofluoric acid for crude Zr or Mo isolation and transfer of Nb from anion exchange column to UTEVA with 0.3 M H2C2O4/ 8 M HCl was used. The UTEVA resin was applied for further decontamination from Zr or Mo by washing with 6 M HCl and final elution of Nb with 0.1 M oxalic acid. Decontamination factor of 90Nb was measured by gamma spectroscopy. Results The developed separation procedure took less than 1 hour. The yield of 90Nb in the final fraction of 0.1 M oxalic acid (400 μL) varied between 95-97% with decontamination factors of 105 and 108 after UTEVA. Conclusions A new separation strategy allowed rapid separation ( 95%) and decontamination factor (>108). This new chemistry provides 90Nb appropriate for following in vivo investigations with 90Nb-labeled PET tracers.

The KLL Auger spectrum of Sm (Z= 62) following the electron capture decay of radioactive Eu-147,Eu-148,Eu-149 atoms in a solid state source was measured with the instrumental resolution of 14 eV. Energies and relative intensities of all the nine basic spectrum components were determined and compared with those of the previous measurement and theoretical predictions. Our absolute Auger transition energy 32627.3 +/- 1.4 eV for the dominant KL2L3(D-1(2)) transition was found to be higher by 16.0 +/- 1.4 eV than that one of the widely used relativistic semi-empirical calculations by Larkins. Taking into account results of our measurements of the L3M4M5((1)G(4)). L3M5M5(F-3(4)), and KL2L3(D-1(2)) Auger lines from both the EC decay and the beta(-) decay for atomic numbers Z= 62 and 64 and also previous experimental data a conclusion is made that the discrepancy found is caused by the "atomic structure effect". The measured value for the KL1L2(P-3(0)/P-1(1)) transition intensity ratio proved strong influence of the relativistic effects on the intensity distribution between the P-3(0) and P-1(1) doublet components. (C) 2011 Published by Elsevier B.V.

We studied in detail the sorption behavior of Ti, Zr, Hf, Nb and Ta on AG 1 anion exchange resin in HF-acetone mixed solutions as a function of organic cosolvent and acid concentrations. Anion exchange behavior was found to be strongly acetone concentration dependent. The distribution coefficients of Ti, Zr, Hf and Nb increased and those of Ta decreased with increasing content of acetone in HF solutions. With increasing HF concentration anion exchange equilibrium analysis indicated the formation of fluoride complexes of group 4 elements with charge -3 and Ta - -2. For Nb the slope of -2 increased up to -5. Optimal conditions for separation of the elements using AIX chromatography were found. Group 4 elements formed MF73- (M = Ti, Zr, Hf) complexes whose sorption decreased Ti > Hf > Zr in reverse order of complex stability. This fact is of particular interest for studying ion exchange behavior of Rf compared to Ti. The advantages of studying chemical properties of Rf and Db in aqueous HF solutions mixed with organic solvents are briefly discussed.

The long-term energy stability of the 7.5 keV and 17.8 keV conversion electrons of the 9.4 keV and 32 keV nuclear transitions respectively in Kr-83m, emitted by solid Rb-83/Kr-83m sources, prepared by evaporation in a vacuum, is investigated using two different spectrometers. The results obtained indicate the principal applicability of these Rb-83 sources for monitoring the stability of the energy scale of electron spectrometers in the 20 keV region at the level of +/- 60 meV for at least two months, which corresponds to the requirement of the new KATRIN tritium neutrino project. Investigations are being continued using sources produced by implantation of Rb-83 ions into different substrates.

The long-term energy stability of the 7.5 keV and 17.8 keV conversion electrons of the 9.4 keV and 32 keV nuclear transitions respectively in 83m Kr, emitted by solid 83 Rb/ 83m Kr sources, prepared by evaporation in a vacuum, is investigated using two different spectrometers.The results obtained indicate the principal applicability of these 83 Rb sources for monitoring the stability of the energy scale of electron spectrometers in the 20 keV region at the level of ±60 meV for at least two months, which corresponds to the requirement of the new KATRIN tritium neutrino project.Investigations are being continued using sources produced by implantation of 83 Rb ions into different substrates.Key words: nuclear transition