Individual contributors became less and less prominent in scientific fields as the discipline itself matured. Some people still hold the public spotlight for their discoveries, like Peter Higgs with the Higgs boson, which several other physicists also theorized around the same time as him.
However, the actual data that ultimately gave Higgs and Francois Englert their Nobel Prize was collected by the Large Hadron Collider, arguably one of the greatest engineering projects that took decades for thousands of scientists to design, build and test.
Subatomic particles aren’t the only things that require large, complex detectors to study. With the help of an underground research facility in South Dakota, a team from Lawrence Berkeley National Laboratory has developed, deployed and tested the world’s most sensitive dark matter detection system.
The project, known as Lux-Zeplin, or LZ, has a history that would give any project manager nightmares. A team of 250 scientists and engineers from 35 different institutions collaborated on the project, whose main detector was delivered to its underground home in South Dakota just before the Covid pandemic forced many of these participants to stay in home institutions for the next two years.
YT video explaining the hunt for dark matter.
Despite all of LZ’s troubles, in December 2021, it officially went live and started collecting data. This data served as the basis for a recent paper, proving that LZ is the most sensitive dark matter detector ever created.
That’s not to say he actually saw dark matter on his first run. Notoriously difficult to detect using any method other than gravity, dark matter remains an enigma to this day. But scientists have developed a detection methodology that they believe will help them understand it better, and it is this technology that forms the basis of LZ’s system.
A giant tank filled with liquid xenon makes up the bulk of the system, along with an array of photomultiplier tubes (PMTs) that can detect when one of the myriad xenon atoms is hit by a particle that could “mimic a matter signal black”. In this case, the atom lights up, which is then detected by one of the PMTs, which can also isolate the spatial area and the direction in which the particle was moving.
If the detector itself were above ground, too many of these particles would create too much noise compared to the dark matter signal, hence why the detector is located below the Earth’s surface at the Sanford Underground Research Facility (SURF). SURF also hosts other sensitive experiments that benefit from the shielding offered by the Earth’s surface, so LZ fits right in with the rest.
So far, LZ is only a few months old, but even these results are exciting the team that originally designed and built the detector. There’s a lot more science to come, however, with the current plan to collect 20 times more data than so far. Given the difficulty of detecting dark matter and the general bias in science that more data is better, this seems like an excellent proposition for finding dark matter if it exists. Perhaps the experiment with the Latin word for light in its name will be the first to shed light on the mystery of dark matter.