Leptons
| Particle | Symbol | Mass (MeV/c2) | Electric Charge |
|---|
| electron | e- | 0.511 | -1 |
| muon | μ- | 105.7 | -1 |
| tau | τ | 1784.1 | -1 |
| electron neutrino | νe | >7.3×10-6 | 0 |
| muon neutrino | νμ | >0.27 | 0 |
| tau neutrino | ντ | >35 | 0 |
Quarks1
| down | d | 5-15 | -1/3 |
| up | u | 2-8 | 2/3 |
| strange | s | 100-300 | -1/3 |
| charm | c | 1300-1700 | 2/3 |
| bottom | b | 4700-5300 | -1/3 |
| top | t | <91,000 | 2/3 |
Gauge Bosons
| photon | γ | 0 | 0 |
| gluon | g | 0 | 0 |
| W-boson | W | 80,200 | 1 |
| Z-boson | Z | 91,170 | 0 |
Some Sample Hadrons
| Particle | Symbol | Mass (MeV/c2) | Electric Charge | Quark Content |
|---|
| positive pion | π+ | 139.6 | 1 | uđ |
| positive kaon | K+ | 493.7 | 1 | us |
| proton | p | 938.3 | 1 | uud |
| neutron | n | 939.6 | 0 | udd |
| lambda | Λ | 1115.6 | 0 | uds |
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