j/ψ meson

The subatomic particle also known as a psion—comprised itself of a charm quark and a charm antiquark bound in a state referred to as “charmonium” (see previously) was discovered independently by two laboratories in Stanford and Brookhaven who made their joint announcement on this day in 1974. Sharing the Nobel Prize in physics two years later for their “November Revolution” for setting of a new era in the study of high-energy physics, the research leaders were able to validate the heretofore theoretical quark model, considered a mathematical fiction—particles with fractional charges and flavours (“spin”)—as a way of classifying and ordering the newly discovered menagerie of constituent, subatomic units.