Newly discovered particles, and what's in them

Quarks, basically. But more charming than usual

Last month the LHCb experiment, at CERN's Large Hadron Collider (LHC), reported the discovery of a new particle. While this received a reasonable amount of attention, it didn't really cause as much excitement as, say, last year's unconfirmed hints of a new particle from the ATLAS and CMS experiments (also at the LHC), which turned out in the end to be just a statistical glitch.

Those hints evaporated when more data came in, as such glitches do. The new particle at LHCb has passed a much higher statistical threshold, and seems to be here to stay. The animation here shows how the signal developed in the data over time as the LHCb experiment recorded and analysed more data. The peak indicating the presence of the new particle, call a I_cc⁺⁺ (pronounced Ksi c c plus plus) is pretty convincing by eye, an impression confirmed by solid statistical analysis. So why isn't there (even) more excitement about this particle? There are good reasons, and they are worth looking into.