High Pressure Gas TPC Development Studies for the DUNE Near Detector

宇宙中的反物质是如此微不足道，以至于我们的世界存在了足够长的时间来进化智能生命。但我们的知识却不是这样说的：根据书本，所有的物质都应该和反物质一起以相等的比例消失。解开这个谜团的唯一关键来自中微子和反（物质）中微子之间的行为差异，这可以通过基于加速器的中微子实验来研究。有了更强大的加速器和更精密的探测器，我们正以前所未有的精度研究中微子的相互作用。深层地下中微子实验（DUNE）是美国的下一代中微子实验，旨在寻找中微子和反中微子之间的微小不对称性，并寻找起源于粒子物理学标准模型之外的物理学的罕见事件。DUNE将通过测量中微子振荡来做到这一点，中微子振荡是一种从费米实验室产生到1200公里外的远探测器（FD）探测到中微子的过程中改变类型的现象。近探测器（ND）复合体由液态氩TPC、由螺线管和量热计封闭的高压气体时间投影室（HPgTPC）和轴上束流监视器组成。这个综合体的设计是为了精确地测量中微子束，并以前所未有的细节研究中微子-核相互作用，以便更好地了解导致振荡测量的相应系统误差。目前正在设计的DUNE ND的HPgTPC将是研究中微子相互作用的最终探测器，因为它具有非常低的探测阈值，全角度接受，并且非常大的高压气体体积提供大的目标质量。这项研究将侧重于气体研究和读出技术的发展，并提供一个技术解决方案，HPgTPC气体质量控制，被认为是一个高度优先事项。该项目将嵌入沃里克TPC平台，为英国加速器中微子气体TPC研发提供强有力的本地支持。这将非常及时地推动英国对HPgTPC概念的进一步研发，并将很好地补充英国对DUNE近探测器项目的贡献。

Antimatter in the universe is so negligible that our world exists long enough for intelligent life to evolve. But our knowledge says otherwise: By the book, all matter should have obliterated together with antimatter in equal parts. The only key to unlocking this puzzle comes from the behavioural difference between neutrinos and anti(matter-)neutrinos, which can be studied by accelerator-based neutrino experiments. With more powerful accelerators and sophisticated detectors, we are on the way to examining neutrino interactions with unprecedented precision. The Deep Underground Neutrino Experiment (DUNE) is the next-generation neutrino experiment in the US designed to look for the tiny asymmetry between neutrinos and antineutrinos and search for rare events that originate from physics beyond the Standard Model of particle physics. DUNE will do this by measuring neutrino oscillations, a phenomenon where neutrinos change type on their way from their production at Fermilab to their detection by the Far Detector (FD) 1200 km away. The near detector (ND) complex consists of a liquid argon TPC, a High-Pressure gas Time Projection Chamber (HPgTPC) enclosed by a solenoid and a calorimeter, and an on-axis beam monitor. This complex is being designed to precisely characterise the neutrino beams and to study neutrino-nucleus interactions with unprecedented details so that the respective systematic errors contributing to the oscillation measurements are much better understood.The HPgTPC of the DUNE ND, currently being designed, will be the ultimate detector to study neutrino interactions due to its very low detection threshold, full angular acceptance, and very large high-pressure gas volume providing a large target mass. This research will focus on the gas studies and readout technology development and provide a technical solution to the HPgTPC gas quality control that is considered a high priority. Embedded in the Warwick TPC Platform, the project will provide strong local support for accelerator-neutrino gas TPC R&D in the UK. It would represent a very timely push for further R&D into the HPgTPC concept in the UK and would complement well efforts to extend UK contributions to the DUNE Near Detector project.