DARK MAtter for Precision experiments (DARKMAP)

我们对宇宙内部运作的最佳理解要求暗物质贡献宇宙总质量的80%左右，在所有天文尺度上塑造其形式。然而，暗物质的基本粒子组成仍然是一个谜，所有试图通过测量或直接观察来解决这个问题的尝试都失败了。现有的实验都集中在寻找暗物质，这些暗物质在地下实验室深处的重原子上散射，假设它的行为像缓慢移动的粒子。这种类型的暗物质被称为弱相互作用大质量粒子（WIMP），其质量是质子质量的倍数。对于质量低于碳原子质量的暗物质，缓慢移动的WIMPs的动量下降到这些实验中使用的重核的反冲阈值以下，并且无法再检测到。如果暗物质轻得多，它的性质就完全不同了，它最好被描述为均匀的流体状物质，而不是大质量粒子云。在这种情况下，寻找弹性散射的实验完全不敏感。这种非常轻的暗物质的行为更像是一种新的力，它对电子和原子核的作用非常微弱，或者影响它们的自旋。在这种情况下，预期的影响是微小的，只能在非常精确的测量基本常数和相互作用中观察到。该项目是一个真正的多学科努力，使高精度的原子物理实验能够寻找暗物质。在过去的几十年中，许多这些实验取得了巨大的进展，使它们的灵敏度提高了许多数量级。这些高精度的实验可以潜在地测量光和非常轻的暗物质相互作用所产生的非常微小的影响。宇宙中这种暗物质产生的理论机制是有帮助的，因为它预测了共振增强的时间依赖信号，如果实验可以设计出来的话。根据具体的相互作用，一个专门的或各种各样的实验可能是正确的策略。为了回答这个问题，考虑到描述高能暗物质所必需的量子场论的复杂结构，将开发一个一致的理论框架。即使高精度的实验是在相当低的能量相比，对撞机实验，甚至一些天体物理过程，这些计算是必要的，以正确地得出这些实验的观测值和观测值之间的相关性。该框架进一步使得不同的实验方法具有可比性，并且现有的限制可以用于优化未来的实验。有了这个在手，我们可以与英国各地的原子物理学家合作，设计一个实验计划，利用高精度实验的未开发潜力来寻找和发现暗物质。

Our best understanding of the inner working of the Universe demands that Dark Matter contributes about 80% of the total mass of the Universe, shaping its form at all astronomical scales. However, the composition of Dark Matter in terms of fundamental particles remains a puzzleand all attempts to solve it through measurements or direct observation have failed to date.Established experiments have focussed on searches for Dark Matter that scatters off heavy atoms in deep underground labs, assuming it behaves like slowly moving particles. This type of Dark Matter is called Weakly Interacting Massive Particle (WIMP) and its mass is a multiple of the proton mass. For Dark Matter masses below the mass of a Carbon atom the momentum of the slowly moving WIMPs drops below the recoil threshold of the heavy nuclei used in these experiments and it cannot be detected anymore. If Dark Matter is much lighter, its properties are fundamentally different, and it would be better described as a homogeneous fluid-like substance instead of a cloud of massive particle. Experiments searching for elastic scattering are entirely insensitive in this case. This very light Dark Matter behaves more like a new force acting very weakly on electrons and nuclei or affecting their spin. In this case the expected effects are tiny and can only be observed in extremely precise measurements of fundamental constants and interactions.This project is a truly multidisciplinary effort to enable the search for dark matter with high-precision atomic physics experiments. Many of these experiments have made enormous progress during the last decades, increasing their sensitivity by many orders of magnitude. These high-precision experiments can potentially measure the very minute effects exerted by interactions of light and very light dark matter. The theoretical mechanism underlying the production of this type of dark matter in the universe helps, because it predicts resonantly enhanced time-dependent signals, if the experiment can be designed to pick it up. Depending on the specific interaction, one dedicated or a variety of experiments might be the right strategy.In order to answer this question a consistent theoretical framework will be developed taking into account the complex structure of quantum field theories necessary to describe dark matter at high energies. Even though high-precision experiments are performed at rather low energies compared to collider experiments or even some astrophysical processes these calculations are necessary to correctly derive observables and correlations between observables for these experiments. This framework further makes the different experimental approaches comparable and existing limits can be used to optimise future experiments. With this in hand we can collaborate with atomic physicists throughout the UK to design an experimental programme exploiting the untapped potential of high-precision experiments to search for and potentially discover dark matter.