On 18 April, the 11th Collaboration Meeting of the MPD Experiment at the NICA Facility started. The three-day meeting is taking place at the Laboratory of High Energy Physics and online. More than 150 participants gathered to discuss the progress in the implementation of the project.

During the opening of the meeting, JINR Vice Director, Leader of the NICA Megascience Project Vladimir Kekelidze noted the successful result of the longest commissioning run in the history of the facility. The session ended in the February this year. “For the first time, all the elements of the accelerator cascade worked properly for more than four thousand hours. As a result of the run, the BM@N Collaboration collected more than half a billion events. It means that the first physical programme at NICA has started”, he highlighted. Vladimir Kekelidze also said that all the magnets of the collider are ready for operation. 80 dipole magnets have already been installed in the arches of the tunnel. Construction works at the facility have been completed and the delivery of engineering equipment is expected. The cryogenic complex of the NICA Project will be put into operation within the next few months. The main electrical substation is already functioning. “Due to external circumstances, there are difficulties with the delivery of finished equipment and the fulfilment of contract terms by our colleagues. Despite this, the MPD Сollaboration finds solutions to these problems, and the project develops,” Vladimir Kekelidze stressed. He also expressed hope that at the end of this year it will be possible to start the technical launch of the collider.

The collaboration’s spokesman Victor Riabov (PNPI) reported on the current status of the collaboration and progress in the implementation of the MPD Project. The project brings together more than 500 participants from 34 institutes of 10 countries. During the meeting, the Institutional Council of the collaboration will consider the candidacy of VBLHEP JINR leading researcher Arkady Taranenko as Deputy Leader of the collaboration. “The collaboration is changing, it grows and develops,” Victor Riabov stressed. The number of publications is increasing. Thus, about 200 articles on physical research, equipment, and software of the experiment have already been published.

According to Victor Riabov, the most difficult and delicate stages in the implementation of the MPD Project will be the cooling of the magnet and its connection to the power supply. Work on the relocation of refrigerators at the technological cryogenic platform and their connection with the rest of the equipment is currently carried out in the MPD Hall. In addition, specialists are adjusting the control and power supply systems of the facility.

Head of the MPD Project at the NICA Accelerator Complex JINR Viacheslav Golovatyuk said that at the end of April the team will start pumping the solenoid to its working vacuum inside the cover. In late May – early June, specialists plan to start cooling the magnet to the temperature of liquid nitrogen. From June to September, work on MPD will be halt so that specialists can paint the walls of the hall for fire safety purposes. Then, from October to December, the project team is going to cool the magnet down to the temperature of liquid helium. Magnetic field measurements are preliminary scheduled for early 2024. The commissioning of the MPD Detector and the first data set are now scheduled for 2025.

All components of the first stage of the MPD Experiment are actively being developed and tested. Speakers will present reports on each system at the meeting. Participants will discuss the software and computing infrastructure of the detector, as well as reconstruction of events in the experiment. Speakers of physical working groups will deliver progress reports. As part of the meeting programme, participants will be able to get acquainted with the status of the works during an excursion to the Nuclotron and MPD Halls, which will take place on 19 April. Recordings of reports will be available on the event’s website at the end of the meeting.