CERN confirms heavy proton cousin Xi-cc-plus after detector upgrade

CERN's LHCb reported the Xi-cc-plus, a particle containing two charm quarks and about four times the mass of a proton, identified in roughly 915 events aided by a 2023 detector upgrade.

CERN's LHCb collaboration announced the observation of a new particle called Xi-cc-plus. The particle contains two charm quarks and is about four times heavier than an ordinary proton. It is very short lived, with an observed lifetime near 45 femtoseconds. The result was presented at the Rencontres de Moriond conference and was enabled by a 2023 upgrade to the LHCb detector. Key facts: - The particle is named Xi-cc-plus and contains two charm quarks. - Its mass is reported as about four times that of a proton and its lifetime is around 45 femtoseconds. - LHCb researchers identified the particle by observing roughly 915 decay events. - The finding was aided by a 2023 upgrade to LHCb equipment and was presented at the Rencontres de Moriond conference. - Xi-cc-plus is reported as the 80th hadron found by LHC experiments and will be described in a forthcoming scientific paper. Summary: The observation offers an empirical test for models of quantum chromodynamics that describe how the strong force binds quarks. The result aligns with theoretical predictions made about two decades ago and will be detailed in a formal paper. The Large Hadron Collider is scheduled to pause operations this summer ahead of further upgrades, which are expected to expand experimental reach in the coming years.