What the X particle looks like still isn't clear, but researchers at CERN say they've made the best detection of it yet.
As atoms and subatomic particles swirl and crash into each other within the magnetic whorl of CERN’s Large Hadron Collider (LHC), the detectors watching their collisions and the high-energy debris they produce turn what they’re seeing into data—a lot of data.
The vast majority of that data is fluff that CERN automatically filters out. But each year that LHC runs, CERN estimates, produces 90 petabytes of saved data—enough to fill up 90,000 typical 1-terabyte hard drives. CERN, in the fashion of a 1960s space opera, stores much of it on giant banks of magnetic tape in a glossy room near the French-Swiss border. It’s too much data for any human to easily sift through.
It’s perhaps unsurprising that hidden gems lie buried deep within these storage banks, waiting to be found. Particle physicists have uncovered one such gem: a strange particle with a strange name, X(3872). If they’re right, it could be a look back into the very earliest flickers of time—what the universe looked like in the first millionth of a second after the Big Bang. They published their findings in the journal Physical Review Letters on January 19.
They’ve only scratched the surface of what this particle looks like. “Theoretical predictions from different groups did not agree with each other,” says Yen-Jie Lee, a particle physicist at MIT, and one of the researchers.
X(3872) sounds like the name of a cryptid, and its previous sightings have been fleeting indeed. The first one came in 2003, when scientists at the Belle experiment, a particle accelerator in Tsukuba, Japan, north of Tokyo, glimpsed X(3872) as they were smashing electrons together. Unfortunately, X(3872) decayed and vanished too quickly for scientists to learn much.
