Discovered almost two decades ago by a Japanese team, the mysterious X particle was detected for the first time in a quark-gluon plasma, or “primordial soup of the Universe”, produced at CERN.
“This is just the beginning of the story”
It is estimated that shortly after the Big Bang, the early Universe was filled with burning quark-gluon plasma. A few microseconds later, it cooled to form the building blocks of all matter in the cosmos. But in the process, a fraction of those quarks and gluons randomly collided to form short-lived X-ray particles. Extremely rare, these have finally been detected in the plasma quarks-gluons from Large Hadron Collider (LHC) by researchers from WITH.
Using machine learning techniques, physicists have analyzed more than 13 billion heavy ion collisions, each generating tens of thousands of charged particles. In this soup of ultra-dense, high-energy particles, the team identified 100 particles X (3872), a figure referring to their individual mass.
« This is just the beginning of the story “, highlighted Yen-Jie Lee, lead author of the study, published in the journal Physical Review Letters. « We showed that we could find a signal. In the next few years, we want to use quark-gluon plasma to probe the internal structure of the X particle, which could change our view of the type of matter the Universe can produce.. »
Particles identified using a powerful machine learning algorithm
First identified in 2003 in a japanese particle collider, X (3872) decays too quickly for scientists to study its structure in detail. However, it is believed that this and other exotic particles could be more easily spotted within a quark-gluon plasma.
Following their training in this ” primordial soup “, the X particles quickly decompose into particles ” girls which disperse. After identifying the key variables defining their decay pattern, the researchers trained a machine learning algorithm to recognize them, then used it to analyze data from the collision experiments of the LHC.
According to the team, it was almost inconceivable that one hundred of these particles could be identified from such a massive dataset. In the future, the researchers plan to collect more in order to establish precisely the internal structure of the X particle.