The Upsilon meson (
) is a quarkonium state (i.e. flavourless meson) formed from a bottom quark and its antiparticle. It was discovered by the E288 experiment team, headed by Leon Lederman, at Fermilab in 1977, and was the first particle containing a bottom quark to be discovered because it is the lightest that can be produced without additional massive particles. It has a lifetime of 1.21×10−20 s and a mass about 9.46 GeV/c2 in the ground state.
|Interactions||Strong, weak, Electromagnetic, Gravity|
|Discovered||E288 experiment (1977)|
|Mean lifetime||1.21×10−20 s|
|Electric charge||0 e|