The European Organization for Nuclear Research (CERN) is a global center for cutting-edge research in particle physics and nuclear physics, hosting the world’s highest-energy particle accelerator-the Large Hadron Collider (LHC). The four large detector experiments (ALICE, ATLAS, CMS, and LHCb) utilize advanced detection technologies to observe and study microscopic phenomena, providing a state-of-the-art platform for the development of advanced particle detection technologies. CERN gathers over 12,000 researchers from more than 70 countries, exemplifying successful international cooperation. Since 1997, NSFC has supported Chinese researchers' participation in major LHC experiments. In 2024, NSFC established the "NSFC-CERN Large Scientific Infrastructure International Cooperation Research Program," managed following the NSFC Major Research Plan mechanism. This initiative, focused on physical research and detector development, funds Chinese researchers participating in international cooperative research at CERN through cultivation projects, key projects, and integration projects, promoting scientific innovation, technological development, talent cultivation, and international collaboration in particle and nuclear physics. 2025 marks the program’s second implementation year.

I. Scientific Objectives

The program supports advanced particle detection technology development and cutting-edge particle and nuclear physics research at the four large detector experiments on CERN's LHC (ALICE, ATLAS, CMS, and LHCb). Objectives include precise measurements of the Higgs boson’s properties to better understand the origin of mass, rigorous tests of the Standard Model of particle physics, the search for new physics beyond the Standard Model, investigation of the matter-antimatter asymmetry, and deeper insights into non-perturbative aspects of Quantum Chromodynamics (QCD), phase transitions, and new states of strongly interacting matter.

II. Core Scientific Issues

1. 1. Precise measurement of the Standard Model and properties of the Higgs boson.

2. 2. New physics beyond the Standard Model and mechanisms of charge-parity (CP) symmetry breaking.

3. 3. The essence of strong interactions and internal hadron structure.

4. 4. Properties of quark-gluon plasma under extreme conditions of high temperature, high density, and low chemical potential.

5. 5. Advanced particle detectors and key technologies of detection and data processing.

III. Project Settings and Funding Areas for 2025

1. 1. Cultivation Projects

Focusing on the aforementioned scientific issues and guided by the overall scientific objectives, the cultivation projects will support exploratory proposals characterized by strong innovation and novel research topics. Priority will be given to the following research directions:

(1) Proposals addressing key scientific issues by formulating novel research topics or experimental methodologies aimed at identifying new physical phenomena or performing precision tests of the Standard Model (including electroweak physics, QCD physics, and parton distribution functions) based on LHC experimental data.

(2) Innovative research on reconstruction and calibration algorithms tailored to physical objects measured and analyzed in LHC detector experiments (e.g., vertices, electrons, muons, photons, tau leptons, jets, heavy-flavor jets, and missing transverse energy), in which algorithms are applied to collision data to enhance measurement accuracy and effectiveness in frontier physics research; proposals focusing on optimizing detector simulation algorithms to significantly improve computational efficiency or precision.

(3) Research focusing on detectors upgraded for the High-Luminosity LHC, including methods of data acquisition and detector calibration to ensure data reliability and accuracy; development of innovative detector reconstruction algorithms to optimize overall detector performance; development of a compact luminosity detector to complement future luminosity measurements; and research on pile-up suppression techniques to improve the measurement precision of relevant physics processes.

(4) Development of novel electromagnetic calorimeters and upstream tracker detectors addressing the specific upgrade requirements for the High-Luminosity LHC. This includes: 1) simulation studies of key physics processes under high-luminosity operational conditions to inform detector design optimization; 2) design of high-precision assembly processes for semiconductor detectors, incorporating artificial intelligence techniques for automated assembly; 3) experimental investigations on luminescence characteristics and high-dose radiation resistance of ultrafast, high-radiation-tolerant inorganic scintillation crystals.

2. 2. Key Projects

Guided by the overarching scientific objectives and centered on core scientific issues, key projects support proposals characterized by innovative research paradigms, robust preliminary research foundations, and strong interdisciplinary synergy. Priority will be given to proposals capable of significantly contributing to the overall scientific objectives and effectively complementing other applications within this program. Specifically, the following research directions are prioritized:

Key Directions in Physics Research:

(1) Further measurements of Higgs boson properties: Expand the scope and depth of measurements involving Higgs boson coupling with vector bosons, including investigations of CP violation phenomena, quantum entanglement effects, and searches for rare decays. Enhance measurement precision of second-generation fermion Yukawa couplings and explore rare phenomena associated with Yukawa couplings. Conduct studies on multi-Higgs processes involving photon final states to strengthen understanding of Higgs self-couplings and search for high-mass resonance states coupled to the Higgs boson.

(2) Precision tests of the Standard Model and searches for physics beyond the Standard Model: Precisely measure diboson processes, especially enhancing measurement accuracy of anomalous triple-gauge couplings and Effective Field Theory Wilson coefficients. Improve the precision of vector boson scattering measurements, particularly exploring and measuring vector boson polarization effects in these processes. Conduct first-time investigations of extremely rare processes such as triboson processes, including Higgs-involved triboson production and 2-to-3 boson scattering processes. Measure multi-top quark processes, investigate their complex dynamics, and further constrain top-quark Yukawa couplings. Effectively explore supersymmetric particles and dark matter particles, specifically targeting difficult-to-probe parameter spaces within supersymmetric theories. Search for Higgs bosons beyond the Standard Model and investigate resonant new particles decaying into dibosons.

(3) Studies of fully heavy exotic hadrons: Search for new exotic states containing four heavy-flavor quarks within bottomonium systems, and precisely measure spin-parity quantum numbers of known corresponding exotic states.

(4) Properties of quark-gluon plasma (QGP) at high-energy frontiers: Utilizing the ALICE Run-3 experiment, investigate the performance and calibration of upgraded detectors such as the Time Projection Chamber and Zero-Degree Calorimeter under continuous readout mode. Systematically study collective behaviors of quark-gluon plasma based on the large statistical datasets from Run-3, covering collective flow, momentum correlations, and polarization effects in strong fields.

Key Directions in Detector Development:

(1) Develop the backend trigger electronics system for the CMS Resistive Plate Chamber (RPC) detector upgrade at Level-1 Trigger, including high-speed readout electronics, development of RPC trigger cluster-finding algorithms, and overall system integration.

(2) Develop the LGAD sensor characterization testing system for CMS Minimum Ionizing Particle Timing Detector upgrade, including a probe-station-based LGAD sensor characterization system, LGAD quality control studies, and firmware and software development and applications for the DAQ system.

(3) Address the upgrade requirements for the reinforcement of the central region of the LHCb electromagnetic calorimeter during LS3 by developing a new electromagnetic calorimeter module. Key tasks include: Design and 3D-printing technology research of tungsten-based absorbers, along with the production and quality control of selected modules; Development of radiation-resistant optical fiber systems; System integration technology for novel electromagnetic calorimeter units, experimental research on calorimeter performance, and development of corresponding testing systems.

(4) Develop new electromagnetic calorimeters and upstream tracker detectors for LHCb's High-Luminosity LHC upgrade, including: Development of ultrafast, radiation-hard GAGG crystals; Development of detector modules with ultra-high coverage, low material budget, and silicon pixel-chip-based detector modules and corresponding system design; Mechanical design development of low-material budget detectors optimized for low-temperature operating conditions.

(5) In collaboration with the ALICE collaboration, develop silicon pixel sensor chips based on Monolithic Active Pixel Sensor (MAPS) technology for the ALICE3 inner tracker upgrade. The sensor chips should feature high spatial resolution, high radiation tolerance, low power consumption, and high temporal resolution. Contributions include participation in the design and characterization of sensor chips for vertex detectors and intermediate tracking layers.

(6) Develop software and algorithms related to the current and upgraded Real-Time Analysis system for the LHCb experiment. Key research areas include: Development and performance studies of large-scale, high-performance parallel computing models for online physics event selection and storage based on Graphics Processing Units (GPUs); Research on detector calibration and alignment technologies, reconstruction algorithm development, and development and performance studies of four-dimensional track reconstruction algorithms under high-luminosity conditions, along with simulation studies of key physics processes.

3. 3. Integration Projects

Integration projects will focus on selecting large-scale detector development projects that have established solid research foundations and require concentrated collaborative efforts for their completion. The prioritized research direction is:

Development of the ATLAS High Granularity Timing Detector (HGTD): This includes characterization and testing of LGAD sensors; performance validation studies of ASIC readout electronics; assembly and testing of detector modules combining LGAD sensors and ASIC chips; development and testing of peripheral electronics systems; development and testing of high-voltage components; system-level performance testing of engineering prototypes; development and application of Data Acquisition (DAQ) systems; and overall detector assembly and commissioning.

Applications for integration projects must comprehensively cover all the research tasks listed above. Applications addressing only partial aspects of these tasks will not be considered.

IV. Funding Plan for 2025

1. 1. Cultivation Projects: Approximately 500,000 RMB per project (direct costs), with a funding duration of 3 years. The research period specified in the application should be from January 1, 2026, to December 31, 2028.

2. 2. Key Projects: Approximately 1.5–2.5 million RMB per project (direct costs), with a funding duration of 4 years. The research period specified in the application should be from January 1, 2026, to December 31, 2029.

3. 3. Integration Projects: Funding up to 10 million RMB per project (direct costs), with a funding duration of 4 years. The research period specified in the application should be from January 1, 2026, to December 31, 2029.

V. Application Requirements and Notices

1.   Eligibility Criteria

(1) Applicants must have experience in undertaking basic research projects.

(2) Applicants must hold senior academic ranks (titles).

(3) Postdoctoral researchers, individuals currently pursuing graduate degrees, and individuals without an affiliation or whose affiliation is not a NSFC host institution are not eligible to apply.

2.   Limits of Parallel Application

(1) An applicant may apply for only one project under this program in the same year.

(2) The total number of NSFC projects that researchers with senior academic ranks (or titles) can apply for or undertake (as the PI or major participants) is limited to two projects. All project categories (Cultivation Projects, Key Projects, and Integration Projects) shall be counted within the number limits.

(3) More requirements can be found in the NSFC 2025 Guide to Programs.

3.   Application Requirements

Applicants and their host institutions shall carefully read and follow the guidelines provided in this call text, the NSFC 2025 Guide to Programs, and the Notice on the Application and Completion of NSFC Projects in 2025.

1.   No hard copy of the application is needed. Applications must be submitted electronically between May 28, 2025, and July 15, 2025, by 16:00.

(1) Applicants shall submit a completed online application to the NSFC’s Grants System (https://grants.nsfc.gov.cn). The procedure is to log into the Grants System as the PI, click the “online submission” button, then click the “new application” button, select "Science Fund for Global Challenges and Sustainability (面向全球的科学研究基金项目)”, and then "Large Scientific Infrastructure (CERN) (重大科学基础设施(CERN))", and choose one project type from "Cultivation Project-Physical Research (培育项目-物理研究)", "Key Project-Physical Research (重点支持项目-物理研究)、"Key Project-Detector Development (重点支持项目-探测器研制)," or "Integration Project-Detector Development (集成项目-探测器研制)," based on the specific research content of the application.

(2) The number of collaborative institutions for cultivation projects and key projects shall not exceed two, and for integration projects, shall not exceed four.

(3) Applicants should independently formulate the project titles, scientific objectives, research content, technical route, and corresponding budget based on the core scientific issues and funding areas of this program. Physical research projects should take an interdisciplinary approach and make significant contributions to the core scientific issues and the overall objectives of the program. Applications that do not meet the requirements will not be accepted.

(4) Applicants shall complete and submit electronic application forms and attachment materials online according to the instructions and outlines provided in the NSFC’s Grants System. The main part of the application shall be written in English. Applications that do not meet the requirements will not be accepted.

(5) For detector development projects, applicants must submit a certificate of collaborative research signed by the spokesperson of the respective experiments of CERN using the attached template. Applications that do not meet the requirements will not be accepted.

 (6) Applicants must submit the English CVs of the applicant and major participants in the attachments.

2.   The host institutions should verify each item of the electronic application package via NSFC’s Grants System and submit all proposals and supplementary documents to NSFC before 16:00 on July 15, 2025. Late applications will not be accepted.  

3.  To monitor the progress of the projects and promote coherent research activities, the Steering Committee and Working Group of the program will organize annual meetings of the funded projects or regular workshops to facilitate communication and coordination. The PIs should participate in such workshops/meetings and make a budget for relevant costs, and are also responsible for coordinating their international research partners to participate in such activities.

4.   Contact Information

Division III, Department of International Programs:

·     Wu Congcong, Li Jia

·     Tel: 010-62325143, 62328487

·     Email: wucc@nsfc.gov.cn, lijia@nsfc.gov.cn

NSFC Grants System technical support:

·     Tel: +86-10-6231 7474

Annexes

·     Template of the certificate of collaborative research