Meet Ξcc+, a new charming proton-like particle discovered by smashing particles at CERN’s Large Hadron Collider beauty (LHCb) experiment.

Pronounced Xi-c-c-plus, the new fleeting particle contains 2 heavy charm quarks and 1 down quark, while the more familiar proton contains 2 up and 1 down quark.

Mass: ~4x that of the proton
Mean lifetime τ: 45 femtoseconds (4.5e-14 seconds)
Charge: +1
Of interest to: Theorists in quantum chromodynamics 😎⚛️

https://home.cern/news/news/physics/lhcb-collaboration-discovers-new-proton-particle
https://lhcb-outreach.web.cern.ch/2026/03/17/observation-of-the-doubly-charmed-heavy-proton-%CE%BEcc/
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