DistantNews
Support us
🇰🇷 South Korea /Health & Science

After 40 Years of Dark Matter Searches, Scientists Detect a Possible Clue

From Hankyoreh · () Korean

Translated from Korean and summarized by DistantNews. Read the original for the full story.

At a glance

News Named sources Ongoing story
  • The LUX-ZEPLIN experiment detected a 248-kiloelectronvolt recoil signal in data collected at a depth of 1,480 meters in South Dakota.
  • Researchers said the signal could indicate a weakly interacting massive particle, or WIMP, more than 200 times heavier than a proton, but they cannot rule out an unexplained interaction involving ordinary matter.
  • The finding has a statistical significance of 2.6 sigma, below the five-sigma threshold for discovery, and researchers are conducting further analysis.

A single flash recorded deep underground has revived the hunt for dark matter, the invisible substance believed to account for most of the matter in the universe. After more than 40 years of experiments, researchers working with the LUX-ZEPLIN detector say they have found a particle interaction that ordinary matter does not readily explain.

The international team, led by the U.S. Lawrence Berkeley National Laboratory, made the announcement after analyzing 220 days of data collected from March 2023 to April 2024. The signal appeared in a June 16, 2023 recording and involved a recoil transferring 248 kiloelectronvolts of energy. That lies well above the low-energy range traditionally examined in these searches.

It is like looking for a needle in a haystack.

— Alvin KamahaThe UCLA professor described the difficulty of detecting a rare dark-matter collision.

LUX-ZEPLIN is installed 1,480 meters underground at the Sanford facility in South Dakota. Its tank contains more than seven tons of cryogenic liquid xenon. Scientists look for the faint flash and charge produced when a dark-matter particle collides with a xenon nucleus. The depth and a surrounding water shield help block interference from cosmic rays, rock and neutrons.

This event is interesting, but we cannot rule out the possibility that it reflects an interaction involving ordinary matter in a way scientists do not yet understand.

— Richard GaitskellThe LUX-ZEPLIN spokesperson cautioned against treating the signal as confirmed dark matter.

The leading candidate in the search is the WIMP, a particle theorized to interact with matter through gravity and the weak force. If the signal came from a WIMP, the particle could be more than 200 times heavier than a proton. The experiment involves 250 scientists and engineers from 39 institutions, including South Korea’s Institute for Basic Science underground research team.

Researchers stress that the result is not a discovery. Its 2.6-sigma significance corresponds to odds of roughly one in 200 that the signal arose by chance, far short of the five-sigma standard, roughly one in 3.5 million. LUX-ZEPLIN spokesperson Richard Gaitskell said the event could still reflect an interaction involving ordinary matter that scientists do not yet understand. The team has already collected three times as much data as it used in the paper and is continuing its analysis.

We are absolutely not claiming that this is dark matter.

— Sam ErikssonThe Bristol University researcher emphasized that the team has not established the signal’s origin.
About this summary

Originally published by Hankyoreh in Korean. Translated, summarized, and contextualized automatically by DistantNews, with a note on how the source frames the story. Not individually reviewed before publishing. How this works.

More Stories

From Our Blog