XENON1T

XENON1T was a dark matter detector located at the Gran Sasso National Laboratory in Italy. It was part of the XENON experiment, designed to directly detect Weakly Interacting Massive Particles (WIMPs), a leading candidate for dark matter. The detector employed a dual-phase time projection chamber (TPC) filled with 3.2 tonnes of ultra-pure liquid xenon.

The principle of operation involved interactions between WIMPs and xenon nuclei. When a WIMP collided with a xenon nucleus, it would produce a small flash of light (scintillation) and free electrons. These signals were detected by an array of photomultiplier tubes. The TPC allowed for precise three-dimensional reconstruction of these events, helping to distinguish potential dark matter signals from background radiation.

XENON1T was one of the most sensitive dark matter detectors ever built. It operated from 2016 to 2018, setting world-leading limits on the WIMP-nucleon cross-section. While the experiment did not find definitive evidence of WIMPs, it significantly constrained theoretical models and paved the way for its successor, XENONnT. The experiment's success was a testament to the meticulous efforts in reducing background noise and achieving unprecedented levels of xenon purity.