Strongest Evidence Yet That Glueballs Exist as Pure-Gluon Particles
Physicists at BES III report the strongest evidence to date that a glueball—made entirely of gluons—exists, identifying X(2370) as a flavor-singlet state with a mass of about 2.395 GeV/c^2 and roughly 90% gluon content, aligning with lattice QCD predictions and awaiting independent confirmation.