The Bottom Quark
In 1977 Leon Lederman leads discovery of a higher mass resonance at Fermilab
Mass of ? (Upsilon) is 9.5 GeV
Example of bottomonium: b b
Again excited state resonances exist
Now studied in great detail in e+e- collider experiments:
- CLEO: studies B mesons (b quark + u,d,s,c)
Soon there will be a round of many new experiments doing B physics