中国科学院大学教授刘倩介绍，实验团队以广西大学自主研制的气体像素探测器为核心部件，搭建 了一组超灵敏探测装置，相当于可拍摄"单原子运动中释放电子过程"的"照相机"，在实验中利用中子源 轰击"照相机"内的气体分子，同时产生原子核反冲与米格达尔电子，探测装置成功"抓拍"到二者形成 的"共顶点"独特轨迹，验证了米格达尔效应，同时还首次测量了该效应截面与原子核反冲截面的比值， 为国际暗物质实验提供关键的校准依据。 （原载于《人民日报》 2026-01-24 06版） 米格达尔效应由苏联物理学家阿尔卡季·米格达尔于1939年首次提出：一个原子的原子核突然获得 能量加速运动时，原子核在反冲过程中的内部电场变化将部分能量转移给原子核外电子，使电子有概率 获得足够能量脱离原子束缚，形成"共顶点"的两条带电径迹。通过这一效应，可以将原本"不可探测"的 低能核反冲信号，转化为"可观测"的电子信号。80余年来，由于探测设备难以精准捕捉这一过程中极其 微弱的电子信号与独特轨迹，中性粒子碰撞场景下的米格达尔效应始终未被实验直接证实。 本次科研成果得益于探测器性能突破。该探测器由广西大学牵头的CXPD合作组历经10余年研发， 2023年 ...

Group 1 - The core achievement of the research is the first direct experimental confirmation of the Migdal effect in a neutral particle collision scenario, marking a significant step forward in the detection of light dark matter [1] - The Migdal effect, proposed by physicist Arkadi Migdal in 1939, describes how energy gained by an atomic nucleus can transfer to outer electrons, allowing them to escape the atomic binding, thus converting undetectable low-energy nuclear recoil signals into observable electronic signals [1] - The breakthrough in this research is attributed to advancements in detector performance, specifically a gas pixel detector developed by Guangxi University, which took over 10 years to create and was completed in 2023 [1] Group 2 - The experimental team utilized a highly sensitive detection device, likened to a "camera" that captures the process of electron release during atomic motion, successfully "photographing" the unique trajectory formed by nuclear recoil and Migdal electrons [2] - The experiment not only validated the Migdal effect but also provided the first measurement of the ratio of the effect's cross-section to the nuclear recoil cross-section, offering crucial calibration data for international dark matter experiments [2]

Core Insights - The research led by the University of Chinese Academy of Sciences, in collaboration with Guangxi University and Central China Normal University, has successfully confirmed the Migdal effect in a neutral particle collision scenario, marking a significant advancement in the detection of light dark matter [1][2] - The Migdal effect, proposed by Soviet physicist Arkadi Migdal in 1939, is considered a crucial physical pathway to overcome the detection threshold for light dark matter [1] - The breakthrough in this research is attributed to the performance enhancement of the detector, specifically the gas microchannel plate pixel detector, which was adapted for ground experiments after over a decade of development [1] Research Details - The experimental team utilized a gas pixel detector developed by Guangxi University as the core component to create a highly sensitive detection device, capable of capturing the electron release process during atomic motion [2] - The experiment involved bombarding gas molecules within the detector with a neutron source, successfully capturing the unique trajectory of the resulting atomic recoil and Migdal electrons, thereby validating the Migdal effect [2] - This research not only provides critical support for breaking the detection threshold for light dark matter but also offers the first measurement of the ratio between the cross-section of the Migdal effect and the atomic recoil cross-section, serving as a key calibration reference for international dark matter experiments [2]