Salemi Chiara P, Foster Joshua W, Ouellet Jonathan L, Gavin Andrew, Pappas Kaliroë M W, Cheng Sabrina, Richardson Kate A, Henning Reyco, Kahn Yonatan, Nguyen Rachel, Rodd Nicholas L, Safdi Benjamin R, Winslow Lindley
Laboratory of Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Leinweber Center for Theoretical Physics, Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Phys Rev Lett. 2021 Aug 20;127(8):081801. doi: 10.1103/PhysRevLett.127.081801.
Two of the most pressing questions in physics are the microscopic nature of the dark matter that comprises 84% of the mass in the Universe and the absence of a neutron electric dipole moment. These questions would be resolved by the existence of a hypothetical particle known as the quantum chromodynamics (QCD) axion. In this work, we probe the hypothesis that axions constitute dark matter, using the ABRACADABRA-10 cm experiment in a broadband configuration, with world-leading sensitivity. We find no significant evidence for axions, and we present 95% upper limits on the axion-photon coupling down to the world-leading level g_{aγγ}<3.2×10^{-11} GeV^{-1}, representing one of the most sensitive searches for axions in the 0.41-8.27 neV mass range. Our work paves a direct path for future experiments capable of confirming or excluding the hypothesis that dark matter is a QCD axion in the mass range motivated by string theory and grand unified theories.
构成宇宙中84%质量的暗物质的微观本质，以及中子电偶极矩的缺失。一个被称为量子色动力学（QCD）轴子的假设粒子的存在将解决这些问题。在这项工作中，我们利用具有世界领先灵敏度的宽带配置的ABRACADABRA-10厘米实验，探究轴子构成暗物质的假设。我们没有发现轴子的显著证据，并给出了轴子-光子耦合的95%上限，低至世界领先水平g_{aγγ}<3.2×10^{-11} GeV^{-1}，这是在0.41-8.27纳电子伏特质量范围内对轴子最灵敏的搜索之一。我们的工作为未来的实验铺平了一条直接的道路，这些实验能够证实或排除暗物质是弦理论和大统一理论所推动的质量范围内的QCD轴子这一假设。
