Scientists from the University of Manchester have played a leading role in the discovery of a new subatomic particle at CERN’s Large Hadron Collider (LHC). The particle, known as the Ξcc ⁺ (Xi‑cc‑plus), is a new type of heavy proton-like particle containing two charm quarks and one down quark.
The result is the first particle discovery made using the upgraded LHCb detector, a major international project involving more than 1,000 scientists across 20 countries. The UK made the largest national contribution to the upgrade, with significant leadership from Manchester.
The newly observed Ξcc ⁺ is a heavier relative of the proton, which was famously discovered in Manchester by Ernest Rutherford and colleagues in 1917–1919. The proton contains two up quarks and a down quark. Details of the Ξcc ⁺ discovery were presented at the Rencontres de Moriond Electroweak conference.