2026年4月6日至12日，第二届PandaX-xT国际开放在李政道研究所成功举办。这是PandaX合作组织自2025年以来举办的第二次国际开放会议。会议吸引了来自美国、英国会议、法国、德国、日本、俄罗斯、捷克、斯洛伐克、澳大利亚、中国大陆和中国台湾地区的近百名研究人员。会议由上海交通大学牛一飞教授、李政道研究所刘江来教授、科梅纽斯大学费多尔·希姆科维奇教授和中国科学技术大学林青教授共同主持。
由李政道研究所牵头、中国锦屏地下运营实验室的PandaX（粒子与天体物理队列实验）项目，旨在通过一系列逐步升级的队列探索暗物质粒子和中微子特性。PandaX-xT被推进为后续吨级超低本底液团队列平台，专门用于寻找暗物质、马约拉纳中微子、低能天体物理中微子以及其他罕见的回应。目前，PandaX-4T实验已于2021年开始运行，合作团队正积极推进未来PandaX-xT重力系统的研发。
Whether neutrinos are Majorana particles—that is, whether neutrinos are their own antiparticles—remains one of the most fundamental open questions in particle physics. Scientists worldwide are searching deep underground for the extremely rare process known as neutrinoless double-beta decay (0νββ), which would provide a crucial test of the Majorana nature of neutrinos. To reliably identify 0νββ, however, it is first essential to precisely measure the spectral shape and half-life of the Standard Model-allowed two-neutrino double-beta decay process (2νββ).
The PandaX Collaboration has been awarded an NSFC-funded international collaborative research grant for a project titled “Development of Key Techniques for Solar Neutrino Measurements with a Deep Underground Xenon Detector.” This project aims to advance neutrino physics by utilizing the facilities at the China Jinping Underground Laboratory (CJPL), the world’s deepest underground laboratory.
PandaX-4T is not just a dark matter detector, as you may be more familiar with. For such a large and exquisite detector, we can explore multiple physics topics. Neutrino physics is one such important direction.
Background neutrinos can elastically scatter with target nucleus (coherently elastic neutrino-nucleus scattering or CEvNS), producing nuclear recoil signals in a dark matter detector that can mimic dark matter signals. This intrinsic background is the so-called “neutrino floor”, which will ultimately limit the sensitivity of dark matter direct detection. On the other hand, it also provides very interesting physics opportunities to study neutrino interactions.
With the extra energy gained from the cosmic rays, sub-GeV dark matter particles can produce visible recoil signals in the detector. We present a new result searching for the cosmic ray boosted dark matter (CRDM) with the PandaX-II full data. This work is motivated by the theoretical paper (PRL. 126 091804), which first pointed out that a sidereal diurnal modulation in signal rate and energy spectrum due to the Earth shielding is expected for low mass CRDM.
On December 24, 2021, the first dark matter search result from PandaX-4T, a liquid xenon detection experiment, was published in Physical Review Letters as the "Editor's Suggestion" [1]. The American Physical Society 《Physics》 reported this PandaX-4T latest result together with another result from the Axion Dark Matter Experiment with a title of "Tightening the Net on Two Kinds of Dark Matter"
A new result on searching of light dark matter (DM) with PandaX-II experimental data was published online in Physical Review Letters on May 28, 2021 with a title of "Search for Light Dark Matter–Electron Scattering in the PandaX-II Experiment "[1]. This is the 6th PRL paper published with PandaX-II data.
