The LUX-ZEPLIN (LZ) Experiment Team today announced the results of its first science campaign; The experiment is the world’s most sensitive dark matter detector, and although there was no dark matter in this first run, the team confirmed that the experiment worked as expected.
The LZ experiment detector consisted of nested tanks of liquid xenon, 1.5 m high and 1.5 m wide, buried under Dakota. The idea is that a dark matter particle passing through space will eventually bounce off one of the xenon atoms, dropping electrons in a flash recorded by the experiment. The tank was buried regarding a mile underground to reduce the amount of background noise. Today’s announcement comes 60 days following live data was collected from December 25 to May 12.
“We are looking for very, very low energy bounces by the standards of particle physics. It’s a very, very rare process, if ever visible,” said Hugh Lippincott, a physicist at the University of California, Santa Barbara and a member of the LZ team, at a press conference today. “You can fire a dark matter particle within 10 million light-years of lead and expect one reaction at the end of that light-year.”
Dark matter is the general term for unknown matter that appears to make up regarding 27% of the universe. It almost never interacts with ordinary matter, hence “darkness” for us. But we know it exists because, although it has never been directly detected, it has gravitational effects that can be observed on a cosmic scale. (NASA breaks down well understood over here.)
There are many candidates for dark matter. One is WIMP, or Weakly Interacting Massive Particle. Unlike others Dark matter hypotheses such as axions or dark photons, which are so small and scattered that they can act like waves, WIMPs would have mass but never interact with ordinary matter. So to unravel it you need a device that pretty much cuts off all the other physics going on.
LZ is very sensitive, which makes it ideal for detecting those transient and infrequent interactions. The experiment is 30 times larger and 100 times more sensitive than its predecessor, the large Xenon Underground Experiment, according to the Sanford Underground Research Facility. Release. Lippincott said the LZ is an “effective onion,” with each layer of the experiment insulated once morest noise that might mask a potential interaction with WIMP.
“The collaboration has successfully calibrated and understood the detector’s response,” said Aaron Manalisay, a Berkeley Lab physicist and LZ team member, at Berkeley Lab. press release. “Since we activated it a few months ago and during the COVID restrictions, it’s really impressive that we’ve already had such significant results.”
Of the many discoveries the LZ experiment made in 60 days, 335 looked promising, but none turned out to be WIMPs. This doesn’t mean there are no WIMPs, but it does eliminate a whole lot of contention. (This is the gist of what dark matter detectors do: Little by little, they remove what crams the particles Not possible is being.) Several physicists recently told Gizmodo They think the next big discovery in particle physics will come from a dark matter detector like LZ.
This scientific race launched what should be a 1,000-day calendar. The last cycle was also opened, so the LZ team was able to observe the behavior of the technology. Since it worked as expected, the next scientific campaign will see its results “salty”, or scattered with false signals, for reduce bias.
Twenty times more data will be collected in the coming years, so maybe cowards will eventually have to confront the music of their own existence. Then once more, they may not have been there at all. We won’t know until we look.
Plus: 10 years following the Higgs boson, what’s the next big thing for physics?
