核物理实验：2025–2026 年度综述

An annual survey of the nucl-ex arXiv category, covering research published from September 2025 – August 2026. Built on a close-reading set of 108 papers and organised into 40 chapters, it maps the year by the field's research sub-directions.

Book framework (share of the year's output):

• Heavy-Ion QCD Matter and Electromagnetic Probes (65.3%) — This cluster focuses on understanding the properties of hot and dense QCD matter created in heavy-ion collisions, using electromagnetic probes, flow phenomena, and chiral magnetic effects to constrain theoretical models.
• Nuclear Reaction Cross Sections and Detector Development (14.1%) — This cluster centers on precise measurements of nuclear reaction cross sections and the development of detectors and experimental techniques for probing nuclear structure and fundamental interactions.
• Hadron Production and Parton Distributions in High-Energy Collisions (9.4%) — This cluster investigates hadron production mechanisms and parton distribution functions in high-energy heavy-ion and proton-proton collisions to map the nucleon structure and collective dynamics.
• QCD Theory, Dense Matter, and Symmetry Studies (5.2%) — This cluster explores theoretical aspects of QCD, including dense matter equations of state, symmetry constraints, and quantum simulation approaches for nuclear systems.
• Neutrinoless Double Beta Decay and Rare Event Searches (3.4%) — This cluster focuses on searches for neutrinoless double beta decay and other rare events, requiring ultra-low background detectors and advanced readout technologies.
• Nucleon Structure and Electromagnetic Form Factors (1.3%) — This cluster examines nucleon and baryon electromagnetic form factors, axial-vector properties, and resonance structure through elastic and inelastic scattering experiments.
• Nuclear Structure, Symmetry Violation, and New Physics Probes (0.7%) — This cluster investigates nuclear structure, isospin symmetry violation, and electroweak symmetry violation using rare atoms, molecules, and dedicated experimental platforms.
• Mass Spectrometry, Simulation Tools, and Detector Calibration (0.5%) — This cluster develops precision mass spectrometry techniques, simulation frameworks, and detector calibration methods for nuclear and particle physics experiments.
• Deep Sub-Barrier Fusion Reactions (0.1%) — This cluster studies fusion reactions at deep sub-barrier energies to probe nuclear structure effects and reaction mechanisms.

Each sub-direction is covered across three chapters — how it framed its questions, the strength of its key findings, and its open debates and frontiers — so the reader gets a traceable picture of what this part of the field actually produced over the year.