Xi-cc-plus Particle (Ξcc⁺)
Context:
Scientists at Europe's CERN laboratory recently announced the discovery of a new subatomic particle named "Xi-cc-plus (Ξcc⁺)" at the Large Hadron Collider (LHC).
It is the 80th new particle identified by the LHC and the first to be discovered following the major 2023 upgrades to the LHCb (Large Hadron Collider beauty) detector.
What is the Xi-cc-plus(Ξcc⁺) Particle?
To understand this new particle, we must look at the basic building blocks of matter:
Baryons and Quarks:
All normal matter, including the protons and neutrons inside atoms, are made of particles called baryons.
Baryons themselves are made up of three smaller, fundamental building blocks called quarks.
Quarks come in six different "flavours" (up, down, charm, strange, top, and bottom).
A "Heavy Proton":
A normal, everyday proton is made of two "up" quarks and one "down" quark.
The newly discovered Xi-cc-plus is essentially a heavier sibling of the proton.
Instead of "up" quarks, it contains two heavy "charm" quarks alongside one "down" quark.
Key Properties:
Because charm quarks are much more massive, the Xi-cc-plus is roughly four times heavier than a regular proton.
It is also incredibly unstable, flashing into existence for only a tiny fraction of a second (about 45 femtoseconds) before decaying.
Why is this discovery significant?
Observing this rare, double-heavy-quark particle provides physicists with a unique laboratory to test Quantum Chromodynamics (QCD).
Understanding the Universe's Glue:
QCD is the theory that describes the "strong nuclear force"—the fundamental force of nature that glues quarks together to form the protons and neutrons that make up the entire observable universe.
Studying how the ultra-heavy Xi-cc-plus behaves helps scientists understand exactly how this "glue" works at a quantum level.
What is LHC?
The Large Hadron Collider is a 27-km long proton-smashing ring running 100 metres below France and Switzerland.
Famously, it proved the existence of the Higgs boson — known colloquially as the “God particle” — in 2012.