Windchime: first steps towards realizing mechanical detector arrays for particle physics

Recent advances in the mechanical sensing technologies provide a novel pathway in searches for dark matter and other particle physics targets. The operations of individual sensors are now approaching the quantum-limited regime, where the sensitivity is set by noise caused by Heisenberg uncertainty. However, the scalability of these devices to large arrays remains a key challenge to be addressed before the full benefit of these sensors can be realized, including improved sensitivity, energy and direction estimation, and background rejection. Here we discuss the initial progress made by the Windchime collaboration, an interdisciplinary group of quantum sensing and particle physics researchers, in the construction and operation of an array of many mechanical sensors to search for dark matter. Such an array will have immediate reach for novel searches for certain ultra-light and composite dark matter particles, and ultimately could be used for direct detection purely through gravity.