Lux-Zeplin experiment becomes world’s most sensitive WIMP dark matter detector

by mcardinal

Bethany Roberts, FISM News


Researchers presented their first scientific results from The Lux-Zeplin (LZ), a next-generation dark matter experiment, on July 7, 2022. The experiment is currently running at the Sanford Underground Research Facility (SURF) in South Dakota.

The experiment is 100 times more sensitive to signals from dark matter particles than the Large Underground Xenon experiment (LUX), which was LZ’s predecessor. The experiment is designed to detect WIMPs or weakly interacting massive particles; these particles are among the top prospects for explaining (and understanding) dark matter. 

The first scientific results published show that LZ has the largest target mass of any WIMP detection experiment to date and is now the world’s most sensitive WIMP dark matter detector.

The collaboration consists of about 250 scientists in 35 institutions in the U.S., U.K., Portugal, and Korea. It received its name from the combination of two previous dark matter detection experiments: LUX (Large Underground Xenon) and ZEPLIN (ZonEd Proportional scintillation in Liquid Noble gasses).

“The collaboration worked well together to calibrate and to understand the detector response,” the physics coordinator, Aaron Manalaysay from Berkeley Lab, said. “Considering we just turned it on a few months ago and during COVID restrictions, it is impressive we have such significant results already.”

The confirmation that LZ is operating successfully allows the experiment to begin full-scale observations. Scientists are hoping that a dark matter particle will collide with a xenon atom very soon. These collisions produce visible flashes of light (scintillation) which are then recorded.

“We plan to collect about 20 times more data in the coming years, so we’re only getting started,” said LZ’s spokesperson, Hugh Lippincott of the University of California Santa Barbara. “There’s a lot of science to do and it’s very exciting!” 

The experiment is working to answer one of the most pressing questions in particle physics: what is dark matter, otherwise known as “missing mass”?

Dark matter is unseen and unproven. Because it does not emit, absorb, or scatter light, the presence of the missing mass is critical to scientifically understanding the universe. According to SURF, dark matter is believed to be about 85% of the total mass of the universe, shapes the form and movement of galaxies, and explains the speculated expansion of the universe.

Dark matter is discerned via gravitational attraction rather than its luminosity. Its existence was first speculated by Swiss American astronomer Fritz Zwicky in 1933. Zwicky discovered that the “mass of all the stars in the Coma cluster of galaxies provided only about 1 percent of the mass needed to keep the galaxies from escaping the cluster’s gravitational pull,” according to Britannica.

Science is much better at explaining what dark matter is not than it is at explaining what it is. NASA writes that observations show there is far too little visible matter in our universe to make up the 27% required by the observations, so something must be filling the space. Dark matter is not in the form of dark clouds of normal matter and it is also not antimatter.

While knowing what it isn’t is helpful, it does not result in any answers. So far, no experiment has uncovered evidence for WIMPs, which is leading some scientists to question the existence of dark matter.

Attention is turning to a newer dark matter candidate called the axion, which would be a millionth or even a billionth the mass of an electron, the Proceedings of the National Academy of Science reported

“These hypothetical particles [axions] are particularly attractive to researchers because they could also solve another outstanding problem in physics, potentially interacting with neutrons to explain why they can feel magnetic fields but not electric ones,” Live Science reported.

The leading hypothesis for what dark matter is, is that it “consists of exotic particles that don’t interact with normal matter or light but that still exert a gravitational pull,” National Geographic reported. “Several scientific groups, including one at CERN’s Large Hadron Collider, are currently working to generate dark matter particles for study in the lab.”

This is why LZ is such an important experiment in the physics field. What is known right now is that LZ is online and taking high-quality physics data and all of its detectors are performing well. The full paper can be found here.

While scientists remain baffled by the mysterious material that holds the universe together, the Bible says that regardless of what dark matter is physically made up of, it was made by God and He is the one ultimately “upholding all things by the word of His power.” (Heb. 1:3)

By faith we understand that the worlds were framed by the word of God, so that the things which are seen were not made of things which are visible” – Heb. 11:3, emphasis added