An international team of scientists have discovered a new subatomic particle known as the Ξcc++ or the Xi-cc++. The particle is from the baryon family, and has two charm quarks and one up quark. The existence of doubly charmed baryons, or baryons with two heavy quarks had been suspected for many years, but not directly observed. Baryons make up most of the observable matter in the universe, which are made up of particles with three quarks. Well known of baryons include protons and neutrons. Baryons observed so far have only had one heavy quark.
Giovanni Passaleva, Spokesperson of the LHCb collaboration said, "Finding a doubly heavy-quark baryon is of great interest as it will provide a unique tool to further probe quantum chromodynamics, the theory that describes the strong interaction, one of the four fundamental forces. Such particles will thus help us improve the predictive power of our theories."
Chris Parkes, deputy spokesperson for LHCb and Head of Accelerator, Nuclear and Particle Physics at The University of Manchester, said "This discovery opens up a new field of particle physics research. An entire family of doubly charmed baryons, related to this particle, now await discovery!"
Dr Patrick Spradlin, a physicist at the University of Glasgow and the leader of the study says, "The properties of the newly discovered baryon shed light on a longstanding puzzle surrounding the experimental status of baryons containing two charm quarks, opening an exciting new branch of investigation for LHCb."
The new particle has been compared to a binary star system with a planet in orbit around it, which is similar to Tatooine from the Star Wars series. The two heavy quarks are the two stars, and the much lighter quark is the planet in orbit. The discovery raises the possibility of finding other baryons with two heavy quarks. The findings have been reported in Physical Review Letters.