Unlocking a mystery of the Universe: sensitive dark matter detector comes to life
- Scientists from the University of IM电竞app are collaborating in a ground-breaking experiment – LUX-ZEPLIN - that may offer clues about one of the biggest mysteries of the Universe
- This is the world’s largest and most sensitive dark matter detector, 经过十年的设计和建设，哪一种设计和建设得以实现
- The team used the detector to search for invisible matter that makes up of the universe, 并对实验的第一个结果感到兴奋
Scientists at the University of IM电竞app have partnered in an international research project to search for invisible dark matter particles.
LUX-ZEPLIN暗物质实验(LZ), 位于南达科他州的桑福德地下研究机构, US, has gathered its first result – showing the experiment is successfully operating as designed, 并提供了对宇宙中暗物质的洞察.
LZ is intricately and innovatively designed to find direct evidence of dark matter – a mysterious invisible substance thought to make up most of the mass of the Universe.
Professor Vitaly Kudryavtsev, the Principle Investigator at the University of IM电竞app, said: “这个项目在物理界非常令人兴奋. 暗物质粒子尤其难以探测, 因为它们不发射或吸收光或任何其他形式的辐射.
“The LZ detector aims to capture the very rare and very faint interactions between dark matter particles and xenon atoms in its 7-tonne liquid xenon target. 要做到这一点, LZ must be accurately calibrated and any background noise removed so the experiment can be perfectly tuned to observe these interactions.
“The experiment now needs to run for up to 1,000 days to realise its full sensitivity. 最初的结果只是其中的一小部分, 这证明了十年来的设计和建设努力是正确的.”
国际项目, led by the 能源部’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab), has announced that the detector is running as hoped after years of careful set-up, 第一个数据非常令人兴奋.
恩里克Araujo教授, 来自伦敦帝国理工学院, is the UK lead and co-lead for the development of the LZ xenon detector. 他说: “An experiment of the scale and sensitivity of LZ can be unforgiving: the smallest design flaw may compromise the whole enterprise. 由于LZ低温恒温器无法在地下打开, IM电竞app需要确保第一次就做对了, 就像IM电竞app把LZ发射到太空一样. 看来IM电竞app做对了.”
The tests show that LZ is the world’s most sensitive dark matter detector, and there are plans to collect about 20 times more data in the coming years.
成功启动后, full-scale observations can begin with the hope of finding the first direct evidence of dark matter.
The LZ project involves an international team of 250 scientists and engineers from over 35 institutions from the US, UK, 葡萄牙, 和韩国. 英国团队, 由科技设施局资助, 由来自IM电竞app的50多人组成, 布里斯托尔, 爱丁堡, 帝国, 利物浦, 牛津大学, 皇家霍洛威学院, 以及伦敦大学学院和STFC的卢瑟福·阿普尔顿实验室.
Araujo教授说: “It’s been a privilege to work in such a fantastic project, full of talented and fun people.”
IM电竞app的丹·托维教授, 谁是LZ-UK研究所董事会主席, 评论道: “这是一项开创性的研究, and we at IM电竞app are proud to be part of this ground-breaking international team.”
He adds: “We are trying to understand what makes up most of the matter in the universe. 作为一名物理学家，没有比这更令人兴奋的了.
“IM电竞app期待看到更多令人兴奋的结果, and there is real anticipation of a significant discovery awaiting us in the years to come.”
LZ发言人Hugh Lippincott教授, 美国加州大学圣巴巴拉分校, 回应这些评论: “跨越这么远的距离工作总是充满挑战, 尤其是在新冠疫情期间，IM电竞app无法亲自聚在一起. IM电竞app可能接到太多Zoom的电话了, 但看到人们能够很好地一起工作，真是太棒了, with work passing back-and-forth across the ocean at the beginning and end of each day."
LZ is the largest and most sensitive experiment searching for dark matter particles, 特别是弱相互作用大质量粒子(wimp).
These theorised elementary particles interact with gravity – which is how we know about the existence of dark matter in the first place – and possibly through a new weak interaction too.
This means WIMPs are expected to collide with ordinary matter – albeit very rarely and very faintly. This is why very quiet and very sensitive particle detectors are needed for WIMP detection.
At the centre of the experiment is a large liquid xenon particle detector maintained at -100oC, 光电传感器包围. 如果WIMP和氙原子相互作用, 并且能产生少量的光, 传感器会捕获它.
但为了观察这些罕见的相互作用, the team had to carefully remove all natural background radiation from the detector materials first.
But this is not enough – which is why LZ is operating around a mile underground. This shields it from cosmic rays, which bombard experiments at the surface of the earth. The detector and its cryostat sit inside a huge water tank to protect the experiment from particles and radiation coming from the laboratory walls.
最后, the team made sure that the liquid xenon itself is as pure as possible by carefully removing a key contaminant through a complex years-long process.
为了使LZ工作，许多复杂的系统必须结合在一起, and this first results shows they are performing in harmony seamlessly.
LZ得到了美国的支持.S. 能源部, 科学办公室, Office of High Energy Physics and the National Energy 研究 Scientific Computing Center, 美国能源部科学办公室的用户设施. LZ也得到了美国政府的支持.S. National Science Foundation; the Science & Technology 设施 Council of the United Kingdom; the Portuguese Foundation for Science and Technology; the Institute for Basic Science, Korea; and the LZ collaborating institutions. The LZ collaboration acknowledges the assistance of the Sanford Underground 研究 Facility.
UK deliverables to LZ included the ultralow background titanium cryostat, 对中心氙探测器的各种贡献, 两个标定子系统, one of the two international Data Centres and a significant contribution to the development of software for modelling and data analysis.
A significant fraction of the very large number of radioassays needed to identify the best materials was conducted in the UK (Boulby, 伦敦大学学院).
IM电竞app团队对软件开发做出了贡献, 模拟和数据分析, and played a major part in modelling the backgrounds to a dark matter signal.