The hunting of the quarkless glueball
Physics Bulletin · 1979
The PLUTO group working on DORIS, the storage ring in Hamburg, is searching electron–positron annihilation events for resonances which would confirm the existence of neutral, unstable, quarkless hadronic matter, believed to come in the shape of 'glueballs'. These were first proposed by Fritzsch and Gell-Mann in 1972 as a consequence of the selfcoupling of gluons, the quanta of the quantum chromodynamics (QCD) field, and they were linked to high energy hadron–hadron interactions by Freund and Nambu in 1975.