Composition | b b |
---|---|
Statistics | Bosonic |
Family | Mesons |
Interactions | Strong, weak, Electromagnetic, Gravity |
Symbol | ϒ |
Antiparticle | Self |
Discovered | E288 experiment (1977) |
Types | 1 |
Mass | 9.46030(26) GeV/c2 |
Mean lifetime | 1.21×10−20 s |
Electric charge | 0 e |
Spin | 1 |
Isospin | 0 |
Hypercharge | 0 |
Parity | -1 |
C parity | -1 |
The Upsilon meson (
ϒ
) 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.