Scientists at the European Organization for Nuclear Research (CERN) discovered two new subatomic particles during experiments using the Large Hadron Collider. As was the case with other never-before-seen particles spotted by CERN's collider, the two new particles were predicted but not proven.
The particles, named Xi_b'- and Xi_b*-, are baryons, which are made up of three quarks bound together by a strong force. Quarks are considered the smallest and most elementary of the known building blocks of atomic particles. But not all quarks are the same; the two new baryons each contain one beauty (b), one strange (s) and one down (d) quark. The b quarks are quite heavy, making the new particles roughly six times more massive than protons.
Though the two new particles possess the same quarks, they're configured slightly differently -- causing them to behave and react in distinct ways.
The discovery was submitted this week to the publication Physical Review Letters for review. One of the scientists who predicted the existence of the two new baryons was excited when he saw the news.
"I saw the title [and] I thought, 'Oh, I predicted those -- I wonder how it turned out?'" Canadian particle physicist Randy Lewis, a researcher at York University, told CBC News. "I looked up their numbers and I said, 'Yeah, that looks a lot like what I predicted -- great!'"
CERN's Large Hadron Collider smashes proton beams together at high speed, creating super-hot explosions of subatomic debris. In the aftermath of the collision, researchers pick out tiny anomalies in the data that explain the behavior and existence of new particles. It's kind of like finding needles in a hay stack, and scientists say they were lucky to find two new particles in one place this go-round.
"Nature was kind and gave us two particles for the price of one," Matthew Charles, coauthor of the new study and particle physicist at Paris VI University, said in a press release.
Charles and his colleagues say discoveries like this are the key to filling in the holes not explained by the Standard Model of particle physics, the basic theory that defines and mediates the dynamics of the known subatomic particles and forces that govern them.
"If we want to find new physics beyond the Standard Model, we need first to have a sharp picture," said Patrick Koppenburg, a particle physicist at the Nikhef Institute in Amsterdam. "Such high precision studies will help us to differentiate between Standard Model effects and anything new or unexpected in the future."