Discovered an extremely rare X particle that existed from the very beginning of the universe

X (3872) is a short-lived matter particle that was recently revived in Switzerland. Researchers at CERN's Large Hadron Collider in Switzerland recently discovered a very rare vanishing particle that they believe dates back to the very beginning of the universe.

They are now called X particles because no one knows exactly what it is, and it is created by colliding billions of heavy ions inside the famous particle accelerator here.

Matter particles have a lifetime of only.1 billionth of a second

Specifically, the CMS Collaboration team, which collects data from the LHC's Compact Muon Solenoid, collided heavy lead atoms at a temperature of about 5.5 trillion degrees Celsius (9.9 trillion degrees Fahrenheit). . Physicists also hypothesize that in the first moments of the universe after the Big Bang, matter was a form of plasma made up of subatomic quarks and gluons, "stuffed together" in a pot of soup that's too hot."

It was only when the plasma cooled a few microseconds after the big bang that familiar protons and neutrons formed, paving the way for the creation of much more massive forms of matter. But before the matter cooled, a number of quarks and gluons collided, forming more mysterious particles, which physicists call X particles.

 They are called X particles because no one knows exactly what it is yet.

X particles are rare today because the universe no longer has the temperature conditions to create it. "If you're interested in the properties of the microsecond universe, the best way to study it is not by building a telescope, but by building a telescope," said Krishna Rajagopal, a particle physicist at MIT. how to build an accelerator."

The team was able to identify 100 X particles of a specific mass, known as X (3872), that lasted for about a billionth of a second before decaying. X (3872) was first found in 2003 through mass difference operations, after which the researchers identified an unexpected amount of mass or energy in their system.

Patrick Koppenburg, a physicist at the Netherlands' National Institute for Subatomic Physics and a member of the LHCb team at CERN, said: "X (3872) is a strange animal. I was in Belle when it was discovered. discovered. We were staring at it without understanding what was going on."

Last year, Koppenburg's research group at the LHCb discovered a new tetraquark, like X (3872), that has a very short lifespan - maybe just over a fifth of a second. Although there are other exotic particles that appear and disappear at the LHC, X (3872) is the first X particle discovered in the quark-gluon plasma produced there.

X-particle generation activities will continue

The team behind this study was also able to mimic the conditions of the early universe by accelerating 13 billion ions. When the particles collided, they produced thousands of short-lived charged particles. Yen-Jie Lee, a physicist at MIT and a co-author of the new study, said: "It's possible that other X particles may be present in the recent data, but researchers don't have a consistent way and best to detect them".

"The first heavy ion in the 'Run 3' operation will begin later this year, and we hope to accumulate more data with the lead collisions in Run 3 and Run 4," Lee wrote. With a much larger data set, we will be able to scale the production enhancement of X in the quark and understand more about its internal structure."

Magnetic core of compact solenoid in factory in Switzerland

Researchers have not yet determined the true "identity" of X (3872), but they suggest that it could be a type of loosely bound mesonic molecule (two subatomic particles called mesons bound together by strong force) or a tetraquark, a type of hadron consisting of four quarks bound together. "So far, mesonic molecules have not been clearly observed, and X (3872) is a candidate," said Jing Wang, a physicist at MIT who led the analysis of the new data. If X (3872) is a mesonic molecule, we think that in the early universe, there must have been many different types of mesonic molecules in addition to ordinary hadrons."

"The more data I look at, the more I believe that X is a continuation of a molecule and a charmonium state because of its incredibly short lifetime," said Patrick Koppenburg. He further notes that: "Our brains cannot represent these things. There is no such thing as one or the other in quantum mechanics. If you can't distinguish the two, then truth must be at the same time both."

It is possible that upcoming activities from the researchers will eventually resolve the identity of X (3872). After that, of course, it would have a more realistic name, and no longer be treated as an anonymous particle X.