Overview:The nuclear physics experiment group aims to investigate the state and properties of nuclear matter formed under extreme conditions in heavy-ion collisions and explore the phase structure of strong interactions through beam energy scan experiments. They also conduct R&D of key technologies on particle detector for nuclear physics experiments.

Members:Feng Liu, Xiaofeng Luo, Yaxian Mao, Hua Pei, Shusu Shi, Xiangming Sun, Yaping Wang, Nu Xu, Zhongbao Yin, Xiaoming Zhang, Daicui Zhou.

Quarks are the fundamentalelementsof matter, and they interact through the strong force mediated by gluons. Quantum Chromodynamics (QCD) describes the interactions between the quarks and gluons. Relativistic heavy-ion collision experiments accelerate heavy ions—stripped of their outer electrons—to near the speed of light and collide them to explore the state of nuclear matter under extreme conditions (such as high temperature, high density, high rotation, and strong magnetic fields), and to understand the phase transition process between quark matter and hadronic matter. Currently, globally operating experiments like LHC/ALICE, RHIC/STAR and sPHENIX, as well as several scientific mega-projects under construction, focusing on heavy-ion beam energy scan, include FAIR/CBM, NICA/MPD, HIAF/CEE, J-PARC-HI, and EIC/ePIC experiments. Thesenuclearphysics experiments aim to investigate the properties and phase structure of nuclear matter formed under strong interactions across different collision energy ranges.

The research topics of the nuclear physics experimental group include:

• Investigating the state and properties of matter formed under extreme conditions in heavy-ion collisions;

• Exploring the phase structure of strong interactions through heavy-ion energy scans;

• R&D on next-generation nuclear physics experimental facilities/detectors and key physics topics;

• Collaborating closely with nuclear theory research to test theoretical predictions.

RHIC/STAR Experiment

In 1999, Tim Halman, deputy spokesman for the RHIC-STAR collaboration, visited Central China Normal University (CCNU), and an agreement was reached for CCNU to join the RHIC-STAR International Collaboration. CCNU became one of the first institutions in China to join the RHIC-STAR collaboration. Over the years, the STAR research team at CCNU has been dedicated to the study of collective flow, correlations and fluctuations, as well as the production of strange and heavy-flavor particles. Systematic measurements have been made on the fluctuations of conserved quantity, the yields of various particles, and the constituent quark scaling behavior of collective flow in relativistic heavy-ion collisions.

Team members：Feng Liu，Xiaofeng Luo，Shusu Shi(Leader)，Yaping wang，Nu Xu.

LHC/ALICEExperiment

Central China Normal University (CCNU) joined the ALICE (A Large Ion Collider Experiment) Collaboration at the European Organization for Nuclear Research (CERN) in 1993, becoming one of the founding members of the ALICE-China group. The ALICE-China group comprises seven leading institutions: CCNU, the China Institute of Atomic Energy (CIAE), Fudan University (FudanU), the University of Science and Technology of China (USTC), China University of Geosciences (Wuhan) (CUG, Wuhan), Huazhong University of Science and Technology (HUST), and Hubei University of Technology (HUT), with CCNU serving as the coordinating institution.

With support from major national funding programs, including the National Natural Science Foundation of China (NSFC), the National 973 Project, the National Key Research and Development Program from the Ministry of Science and Technology (MoST), and significant projects from the Ministry of Education (MoE), the ALICE-CCNU team has made pivotal contributions to the ALICE experiment. These efforts include the research and development (R&D) of large-area photodiodes, front-end electronics, and data acquisition systems for the lead tungstate crystal-based Photon Spectrometer (PHOS), the construction of a high-performance supermodule for the Shashlik-based Dijet Electromagnetic Calorimeter (DCAL), and collaboration with CERN on developing high-speed, scalable readout motherboards for the DCAL, EMCAL, and PHOS detectors.

The ALICE-CCNU group also played a crucial role in the design and physics performance studies for the second-generation Inner Tracking System (ITS2) detector. They collaborated with CERN on the development and characterization of the ALPIDE silicon pixel chip, utilizing Monolithic Active Pixel Sensor (MAPS) technology. CCNU was responsible for integrating, producing, installing, and commissioning one-fifth of the ITS2 silicon pixel modules. The team also contributed to the design and performance evaluations for the forward muon spectrometers and developed the electronic motherboard for the Forward Muon Tracker (MFT).

Currently, the team is actively involved in developing the third-generation Inner Tracking System (ITS3) using flexible silicon pixel technology and the Forward Calorimeter (FoCal). In addition, the group is contributing to R&D for the next-generation ALICE3 detector, scheduled for deployment in 2035. The team has also developed robust software frameworks for analyzing heavy-flavor hadrons, heavy-flavor muons, jets, and correlation studies, along with key roles in data acquisition, quality control, calibration, and reconstruction for ALICE.

In terms of physics research, the group has precisely measured heavy-quark transport properties in the quark-gluon plasma (QGP) at the TeV energy domain and has discovered novel physical phenomena in small system collisions. These significant achievements have been prominently featured in CERN Courier, CERN News, and the Recent Highlights on the ALICE official website. The group members have presented multitimes their findings at CERN Forums, contributing to the global high-energy physics community. Since the start of LHC operations in 2009, the ALICE Collaboration has published nearly 500 peer-reviewed articles, with the ALICE-China group accounting for more than 10% of the key contributions.。

Team members：Yaxian Mao，Hua Pei，Zhongbao Yin，Xiaoming Zhang(Leader)，Daicui Zhou，Chaosong Gao，Guangming Huang，Dong Wang，Yaping Wang，Ping Yang.

NICA/MPDExperiment

The Nuclotron-based Ion Collider fAcility (NICA) is a large-scale heavy-ion collider project under construction at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. It aims to conduct high-luminosity gold-gold nucleus collisions at an average per-nucleon energy of 2.5–11 GeV. This facility will createnuclearmatter with extremely high temperatures and the maximum net-baryon density in laboratory, enabling the study of the QCD phase diagram and the search for the critical point of phase transition.

One of its core experiments is the Multi-Purpose Detector (MPD), which focuses on investigating properties of the createdhot and dense nuclear matter and QCD phase structure in heavy-ion collisions. The NICA/MPD international collaboration was officially established in April 2019, with eight major Chinese institutions as founding members, including Central China Normal University (CCNU), which joined as an official member from the outset. Supported by the National Key Research and Development Programs of China and other scientific funding projects, CCNU, in collaboration with the other Chinese groups, has been conducting research since 2020 on key technologies for silicon pixel detectors and critical scientific questions at the NICA energies.

Teammembers：Feng Liu,Xiaofeng Luo,Shusu Shi,Xiangming Sun,Yaping Wang(Leader).

FAIR/CBMExperiment

FAIRAccelerator Facility：Near Frankfurt airport, a major construction of a huge scientific headquarter, next to the existing heavy-ion facility GSI, is under way. This is the next generation high luminosity accelerator complex FAIR “Facility for Antiproton and Ion Research”. Once completed, now scheduled in 2021, the facility will provide the highest luminosity beams from proton to all stable nuclei on the period table, to cover full four scientific pillars including hadron structure, high-density nuclear matter, astrophysics and the equation of state of nuclear matter at high baryon density. For heavy ion beams, the FAIR will be able to accelerate the Au-beam for the range of center of mass energyper nucleon pairof2.4≤ √s≤4.9 GeV.

CBM Experiment：The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at neutron star core densities, and the search for phase transitions, chiral symmetry restoration, and exotic forms of (strange) QCD matter. The CBM detector is designed to measure the collective behavior of hadrons, together with rare diagnostic probes such as multi-strange hyperons, charmed particles and vector mesons decaying into lepton pairs with unprecedented precision and statistics. Most of these particles will be studied for the first time in the FAIR energy range. In order to achieve the required precision, the measurements will be performed at reaction rates up to 10 MHz. This requires very fast and radiation hard detectors, a novel data read-out and analysis concept including free streaming front-end electronics, and a high performance computing cluster for online event selection. Several of the CBM detector systems, the data read-out chain and event reconstruction will be commissioned and already used in experiments during the FAIR phase 0. The unique combination of an accelerator which delivers a high-intensity heavy-ion beam with a modern high-rate experiment based on innovative detector and computer technology offers optimal conditions for a research program with substantial discovery potential for fundamental properties of QCD matter.

Team members：Feng Liu,Xiaofeng Luo(Leader),Shusu Shi,Xiaoming Zhang,Yaxian Mao,Zhongbao Yin,Daicui Zhou.

Central China Normal University is also official membersof the U.S. RHIC/sPHENIX experiment, the U.S. EIC/ePIC experiment, and China’s CSR/CEE collaborations. The CCNU team has been contributing to these experiments on particle detector R&D and key physics research.