Elementary ParticlesLeptons| 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| positive pion | π+ | 139.6 | 1 | | positive kaon | K+ | 493.7 | 1 | | proton | p | 938.3 | 1 | | neutron | n | 939.6 | 0 | | lambda | Λ | 1115.6 | 0 | |
For each of these particles, except the photon, gluon, and Z-boson, there is an antiparticle with the same mass and opposite charge. In most cases the antiparticle is denoted by an overbar over the particle symbol.
Note 1:
Because quarks cannot be isolated, the masses given for them are approximate.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2023, Columbia University Press. All rights reserved.
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