On 10–13 September 2024, China hosted the second Russia–PRC Joint Workshop on the NICA Facility, a flagship project of the Joint Institute for Nuclear Research. The event was held with the support of the Chinese consortium of organizations participating in the international collaboration created to build the Multipurpose Detector (MPD) at the NICA Collider and conduct experiments at it. The MPD Facility is scheduled to be fully constructed and launched in 2025. The serminar’s four-day scientific programme included meetings in Qingdao and a discussion session in Beijing.

Research groups from Shandong University, Fudan University, Central China Normal University, the University of Science and Technology of China, and Tsinghua University in Beijing actively participated in holding the scientific session in Qingdao. The main organizers were Professors Chi Yang from Shandong University and Zebo Tang from the University of Science and Technology of China. Professor Yin Wong from Tsinghua University organized the discussion session in Beijing with the support of representatives of the Institute of Modern Physics of the Chinese Academy of Sciences and the University of the Chinese Academy of Sciences.

The main purpose of the joint workshop was to bring together relativistic nuclear physics experimentalists and theorists from China and JINR to discuss the MPD Experiment at the NICA Collider, including the latest achievements, work plans, capabilities, and further modernisation. The parties talked about the following key topics:

• construction progress and operation plans for the MPD Facility at NICA;
• proposed physics tasks and preparation for the analysis of MPD’s first experimental data;
• the recent achievements and results in studying nuclear matter at high baryon densities in experiments at the RHIC Collider;
• the first results of the BM@N Experiment at the NICA Collider;
• the goals and opportunities of modernising the MPD Facility’s detectors.

The first day of the meeting in Qingdao was devoted to discussing the progress and prospects of the development of the MPD Experiment at the NICA Accelerator Complex. The speakers presented overviews of the ongoing assembly and integration of various MPD detector subsystems and of the results of detailed modelling of physical measurements at the facility, such as the study of particle polarisation and spin alignment, hyperon and hypernucleus creation. Other topics included the progress of creating the MPD engineering systems, including the magnetic system, and the the internal track system (ITS) in collaboration with colleagues from the Classical University of Central China. At the end of the first day, the participants discussed options for updating the time projection chamber (TPC) of the MPD Detector, including using new reading chambers. Colleagues from China shared their experience of participating in modernising the detector subsystems of the STAR Experiment at the Relativistic Heavy Ion Collider (RHIC, BNL, USA), which preceded the second scanning programme of the interaction energy of heavy nuclei covering the energy range from 3 to 27 GeV. The presented results indicate both significant progress in implementing the large international MPD-NICA Project and the interest of scientists from Chinese institutes and universities in this project.

The second day of the seminar focused on theoretical and experimental research in physics of relativistic heavy ion collisions at the energies of the NICA Accelerator Complex. The specialists discussed the latest results of theoretical and experimental studies of the phase diagram of strongly interacting matter at high baryon density, along with the search for new phase transitions and a critical point. The latest measurement results of the STAR Experiment, including global hyperon polarisation, collective azimuthal fluxes, and hadron output, light nuclei, and hypernuclei, were reviewed. Another topic was the issue of using machine learning methods to study various physical signals in heavy-ion collision physics, the possibility of making new measurements of electromagnetic signals of strongly interacting matter, and the implementation of a nuclear collision energy scanning programme at the NICA Accelerator Complex for various nuclear systems. The scientists discussed the first results of the BM@N Experiment on measuring strange particle and collective azimuthal proton flux outputs in Xe+Cs(I) collisions at 3.8 AGeV. The progress and research programme of the new Cooling-Storage-Ring External-Target Experiment (CEE) at the HIRFL Accelerator Complex (Lanzhou, China) were presented as well.

The results indicate progress in understanding the processes occurring in nuclear collisions and provide a basis for further research. Scientific groups from China showed great interest in playing an even more active role in the MPD Experiment. Studying collisions of various nuclear systems at the NICA Complex is expected to significantly expand the results of the nuclear collision energy scanning programme at the RHIC Collider, which finished in 2021. After the shutdown of the RHIC Collider in 2025, NICA will be the world’s only centre that allows studying relativistic heavy ion collisions at 2-11 GeV.

The third day of the meeting in Qingdao was devoted to discussing the further development prospects of the MPD Experiment and its detector subsystems, along with planned and promising physics research. Other topics included the opportunities of operating the MPD Facility in experimental mode using a fixed target, proposals for upgrading the front part of the detector (including goals and possible solutions), and the creation of a new time-of-flight system for forward velocity measurements. Each day ended with sessions dedicated to exchanging opinions about the presentations, holding discussions, and summarising the day’s results.

On the last day, the participants met at Tsinghua University, Beijing, to review the progress of cooperation between JINR and China as part of the NICA Project and assess further development prospects of the MPD Detector. The workshop was an important event for discussing the current achievements and development prospects of the NICA Project, along with strengthening cooperation between scientists.

As a result of the discussions, the participants decided to regularly hold similar seminars in China and JINR in order to further discuss a wide range of issues and strengthen ties between scientists from JINR’s Member States and China. A working group will be established to discuss the physics programme and design selection of the front spectrometers of the MPD Facility, under development as part of its upgrade, with the ultimate goal of creating their conceptual design.