Next-generation dark matter detector gets approval
15 February 2017
Construction will begin on a next-generation dark matter detector and the UK will take a leading role, providing vital hardware with support from the STFC.
The LUX-ZEPLIN (LZ) experiment will be built almost a mile underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota. It’s considered one of the best opportunities to discover whether theorised dark matter particles, known as WIMPs (weakly interacting massive particles), actually exist.
Officials from the US Department of Energy have now approved the final design, allowing for construction to begin with a completion target of April 2020. The experiment has 220 participating scientists and engineers who represent 38 institutions around the world. UK scientists make up a quarter of the collaboration and are supported by the Science and Technology Facilities Council (STFC).
Henrique Araújo, from Imperial College London, said: “We are looking forward to seeing everything come together after a long period of design and planning.”
LZ will be at least 50 times more sensitive to finding signals from dark matter particles than its predecessor, the Large Underground Xenon experiment (LUX). The new experiment will use 10 metric tons of ultra-purified liquid xenon, to tease out possible dark matter signals. Xenon, in its gas form, is one of the rarest elements in Earth’s atmosphere.
LZ is designed so that if a dark matter particle collides with a xenon atom, it will produce a prompt flash of light. The light pulses are picked up by a series of about 500 light-amplifying tubes lining the massive tank, over four times more than were installed in LUX, which will carry the telltale fingerprint of the particles that created them.
UK scientists are contributing hardware for most subsystems and the vessels that will surround the liquid xenon are also the responsibility of the UK participants. They will be built with the world's most ultra-pure titanium to reduce background noise.
Onsite assembly and installation will begin in 2018.