News of the NICA project

At an extended Director's meeting at VBLHEP

On 14 October, JINR Director Grigory Trubnikov announced the appointment of Andrey Butenko as Acting Director of VBLHEP and appreciated him for agreeing to take on additional greater responsibility.

Andrey Valerievich Butenko was born on 17 April, 1974 in Dubna. After graduating with honors from the Moscow State University of Civil Engineering in 1996, he worked his way up from an engineer in Beam Department of LHE to Chief engineer of the Nuclotron, Head of VBLHEP Accelerator Division and Deputy Director of VBLHEP. In 2012, A.V.Butenko successfully defended his Ph.D. thesis "Modernization of the vacuum system of the Nuclotron and acceleration of low-intensity Xe beams at the VBLHEP accelerator complex".

During his work at the Laboratory, A.V.Butenko actively participated in the work on the Nuclotron-M project, supervised the construction and launch of a new fore-injector for the light ion linear accelerator LU-20, of the Heavy Ion Linear Accelerator of the NICA Injection Complex, supervised the design, assembly and commissioning of the NICA Complex Booster Superconducting Synchrotron. He is co-leader of the Nuclotron-NICA project on the development of the NICA/MPD accelerator-experimental complex, aimed at searching for new phenomena and studying the processes of phase transitions of nuclear matter in high energy heavy ion collisions. A.V.Butenko is the author and co-author of more than 130 scientific papers. He was awarded 5 JINR prizes, Certificates of Honor and a Medal of the Ministry of Education and Science of Russia for his papers. He is an acknowledged expert in the field of superconducting cyclic and linear ion accelerators, in carrying out theoretical and experimental research in the field of ion beam dynamics in superconducting synchrotrons. The main task for the entire Laboratory team today is the implementation of the major project decisions and the launch of the NICA/MPD complex in its basic configuration.

Heavy ion beam accelerated for the first time

According to Deputy Head of the VBLHEP Accelerator Division Anatoly Sidorin, during the current session at the NICA accelerator complex, for the first time, the operation of the full set of heavy ion accelerators, including an electron-string ion source, a heavy ion linear accelerator, a booster and the Nuclotron, was implemented. The intensity of the xenon heavy ion beam accelerated in the Nuclotron is approximately 10⁷ particles.

"Within the framework of the session, the staff of the complex tested the SOCHI applied station on argon ions. This station on the extracted beam will irradiate chips in the future. The ion source, linear accelerator and booster were adjusted to accelerate argon and xenon ions. After acceleration in the booster, xenon ions were recharged to the state of bare nuclei, injected into the Nuclotron and stable circulation of the beam accelerated to an energy of about 3 GeV/nucleon was obtained," Anatoly Sidorin said.

Collaboration between NICA and IBMP RAS

The target laboratory platform for joint work at the NICA accelerator complex is developed at JINR by the leading Russian organization for space biology and medicine problems, responsible for the implementation of the programme of biomedical research and experiments on board the ISS Russian Orbital Segment, the Institute for Biomedical Problems of the Russian Academy of Sciences (IBMP RAS).

The basis for the establishment of the laboratory was laid long ago: at the DLNP JINR technical site there is building No. 73 that is on the balance sheet of IBMP RAS. In this building, an extensive cycle of work to study the biological effects of ionizing radiation, including on the central nervous system was carried out. In particular, in 2015-2016, researchers of IBMP RAS extensively carried out experiments on the irradiation of small laboratory animals, and later primates at the Nuclotron.

A major overhaul of the building is scheduled for 2023. A joint project on modernization of the building with IBMP RAS has already been developed that is currently under the coordination with supervisory authorities. After the modernization, innovative equipment for research in the field of space biology and medicine, as well as radiation materials science, will be installed in the building. The equipment stock will include unique facilities specially designed to solve problems in the field of simulating several factors of space flight in ground conditions.

"A large complex of analytical equipment by modern standards will be installed in the building that will be developed with the involvement of funds from external targeted programmes, government contracts and grants," Deputy Head of the VBLHEP Department of Scientific and Methodological Research and Innovation Oleg Belov said. "Expansion of the Laboratory base implies involving new, primarily young employees with a scientific degree to participate in joint work." As to him, IBMP RAS is not the only organization that intends to develop a common platform for joint work at NICA, but it will be much easier for this scientific centre to establish a target laboratory, since it already has its own building on the territory of JINR.

Results of the meeting of the NICA Coordination Committee

On 16 November, a regular meeting of the NICA Project Coordination Committee was held at the Institute. In his welcome speech, Grigory Trubnikov briefly spoke about the current activities of the Institute. A.V.Butenko reported the current status of the session at the VBLHEP accelerator complex. At present, the ₁₂₄Xe²⁸⁺ xenon ion beam is accelerated in the Booster to 260 MeV/nucleon and injected into the Nuclotron. The injection chain, including the Booster, produces a beam with stable parameters. The system for correcting the Booster's orbit in a dynamic mode has been put into operation - in the entire operating range of currents that is a significant result of the scheduled development of the facility. Nuclotron systems are tested and work is underway to obtain a stable mode of operation with the xenon ion beam. The session will most likely be extended until mid-January 2023; physicists, the staff of the Accelerator Division and the engineering services of the Laboratory are ready for this.

During the discussion, Grigory Trubnikov proposed to prepare and consider the issue of upgrading the Nuclotron at the next meeting of the Coordination Committee or at a separate seminar. The Coordination Committee supported this proposal.

M.N.Kapishin reported that the BM@N facility had been fully tested and was ready to obtain the beam.

A.V.Dudarev spoke about the status of the general contractor agreement with the STRABAG Company. At present, a supplementary agreement is currently prepared on the further work to complete the construction of building No.17. At the construction site, there are delays in implementing work related to delays in the supply of engineering equipment: ventilation, cooling and power supply systems. The deadline for completion of the essential work at the facility is the end of July 2023.

S.A.Kostromin provided an overview of the main risks and critical work for installation of the Collider and registration of the first collisions of beams circulating in it.

V.M.Golovatyuk presented the status of the construction of the MPD detector. The key stage is currently cooling down and launch of the superconducting solenoid, the start of work is scheduled for February 2023. The most of the work on the assembly and testing of detector systems is carried out in accordance with the overall work plan.

V.D.Kekelidze presented a general overview of the progress in development of the NICA complex and the resources required for it. An analysis of the resources expended and the overall progress of the work amounts to 86% as the total percentage of the project completed.

A.S.Sorin delivered a report on the implementation of the Pilot Programme of Special-Purpose Funding for Research Teams from the JINR Member States Acting within the NICA Megascience Project in 2022.

During the discussion, as noted, the MPD Collaboration is approaching the most crucial stage - the stage of data set. Given the scale of the physics programme, it can be implemented only by joining the efforts of the expert community throughout Russia with the participation of foreign colleagues. In this regard, the targeted and at the same time widespread in the professional community programme to support collaboration participants is very relevant at present. The Coordination Committee recommended organizing a similar support programme in 2023 at the expense of the JINR budget.

Progress in constructing equipment for MPD

One of the basic subsystems of the MPD basic configuration at the NICA accelerator complex is the Time of Flight system (TOF). Its task is to discriminate types (masses) of secondary particles produced as a result of ion collisions in the NICA collider.

In 2019, the mass production of MPD TOF detectors and modules was organized and put into operation in VBLHEP. 280 detectors and 28 modules had to be manufactured and tested. Young employees/laboratory assistants were invited to the group for mass production that quickly learned the rather complex and demanding assembly process of MRPC. In addition to young technicians, the TOF assembly team has been enhanced by experienced engineers that optimize the production process. Due to the coherence of the developed team, in September 2022, the production of 280 MRPCs detectors was completed. As of November 2022, the assembly of 24 modules out of 28 required for the MPD TOF system was completed. According to the production schedule, all MPD TOF modules will be produced by April 2023.

To put the Time of Flight system into operation, it is necessary not only to assemble all the modules, but also to prepare all service subsystems, such as a low- and high-voltage power supply systems, a data acquisition system, a slow control system and a gas supply system. The MPD TOF gas system has been developed by engineers at the Warsaw University of Technology. As a first prototype, a similar system has been assembled for a stand for testing TOF modules on cosmic radiation.

Considerable progress was made in 2021-2022 in the development of software for simulation and processing of MPD TOF data. The installation of the modules will start in the autumn of 2023, followed by the commissioning of the TOF system.

SPD: preparation for the project plan is under completion

The project plan of the SPD experiment is based on the preliminary studies during the development and investigation of the properties of prototype units of detectors and SPD subsystems. This work has been carried out not only at various stands at JINR sites, but also outside JINR.

The construction of the SPD facility is supposed to be carried out in two stages: at the first stage, the basic configuration for measurements with polarized beams of protons and deuterons at low collision energies and luminosity far below the nominal one will be developed. The facility will consist of a muon system, a straw-tube based tracking system, a central detector based on Micromegas cameras, zero-degree calorimeters and beam-beam counters (BBC). The complete configuration required for the implementation of the main task of the SPD - the research of the polarized gluon structure of nucleons will be completed by the second phase of the project and will include a silicon vertex detector, the Time-of-Flight system, an electromagnetic calorimeter and an aerogel-based detector. The project plan of SPD will be presented at the winter session of the updated PAC for Particle Physics in January 2023.

News from BM@N Collaboration

In the experiment on the research of baryonic matter at Nuclotron (BM@N), preparations for a session to recruit interactions of CsI target nuclei with a xenon ion beam accelerated at the booster-Nuklotron complex are under completion. This will be the first physics session with a full configuration of the BM@N tracking system.

On 13-16 September, VBLHEP hosted the 9th meeting of the BM@N Collaboration. Reports on the status of the BM@N experiment, on the preparation of the entire facility and individual detectors for the upcoming session on studying the interactions of CsI target nuclei with a Xe ion beam are presented. The programme of physics research in the upcoming session, the readiness of the interaction recovery algorithms and the experimental software to obtain and monitor a large amount of data were also discussed. A separate session of the meeting was dedicated to the results of the analysis of previously registered interactions of carbon and argon nuclear beams with targets in order to obtain experimental data on the yield of charged pions, L-hyperons and light nuclear fragments.

Magnet concept for SPD

On 2 December, VBLHEP hosted a seminar "Superconducting Magnet for the SPD Detector". Speaker E.E.Pyata (BINP SB RAS, Novosibirsk) presented the concept of a magnet for the SPD experiment at the NICA Collider. The cryostat of the magnet has a cylindrical shape with a length of 4 m, an inner diameter of the shell of 3.3 m and a thickness of 25 cm. It will be fixed inside a steel yoke. Due to the small thickness of the cryostat, the "cold mass" of the magnet is held on triangular hangers that fasten it only to the cryostat flanges. The system of current leads is brought to the upper platform of the SPD detector, where the cryogenic equipment will be positioned. The superconducting wire is produced by extruding Rutherford-type NbTi/Cu eight-core cable into a high-purity aluminum matrix that ensures a high level of conductor stability and a high average thermal conductivity of the winding. It is proposed to use an indirect cooling system for the superconducting winding and the reference cylinder.

This system operates based on the natural convection of two-phase helium (thermosyphon effect) that allows to avoid emergency energy extraction from the superconducting winding during a short-term power outage in the experimental hall. In general, the technical solutions in the chosen design of the magnet correspond to modern trends in production of wide-aperture superconducting magnets and the reliability of operation is confirmed by the successful experience in the development and operation of previously produced magnetic systems, such as the magnets of the experiments ATLAS and CMS (CERN), KEDR (Institute of Nuclear Physics) and others.

Based on materials
www.jinr.ru and NICA Bulletin