Key Points
- Scientists at the LHC have measured the quantum properties of rare “tetraquark” particles made of four quarks.
- The main goal is to understand if these particles are tightly bound single units or loosely connected pairs.
- The study focused on a unique family of tetraquarks made entirely of heavy “charm” quarks.
- By analyzing how the particles decay, researchers determined their fundamental characteristics.
Scientists at the Large Hadron Collider (LHC) are getting closer to understanding some of the universe’s most mysterious particles. A new study published in Nature by the CMS collaboration has measured the fundamental properties of a strange family of particles known as tetraquarks, which are composed of four quarks.
While most familiar matter, like protons and neutrons, is made of two or three quarks, the LHC has confirmed the existence of exotic particles made of four or even five. A major puzzle for physicists is figuring out exactly how these particles are built. Are they a single, tightly-bound unit, or are they more like two separate particles loosely stuck together?
To get answers, the CMS team focused on a particularly interesting family of three tetraquarks. What makes them special is that they are composed entirely of heavy “charm” quarks and their antimatter counterparts.
Studying these “all-charm” tetraquarks provides a cleaner, more direct way to test theories about the strong nuclear force—the fundamental glue that holds atomic nuclei together.
By analyzing data from particle collisions between 2016 and 2018, the researchers studied how these tetraquarks decayed, or fell apart. This process enabled them to measure key quantum properties, such as spin and parity. The results of these measurements provide a powerful clue about the particles’ internal structure.
The findings strongly suggest that these tetraquarks are tightly bound objects, not loosely connected pairs. While not the final word, it’s a major step forward in decoding the nature of exotic matter and the powerful forces that govern our universe.
