Key Stage 5
Meaning
Antimatter is a material made from antiparticles, which when in contact with matter will annihilate one another to produce gamma ray photons or other high energy particles.
About Antimatter
- Many particles of matter have antimatter counterparts which have the same mass but opposite electrical charge.
- During pair-production a particle and its antimatter counterpart appear.
- Most antiparticles are given the name of their counterpart particle with the addition of the prefix anti. However, the antiparticle counterpart of the electron is known as the positron.
| Antiparticle | Composition | Charge/e | Strangeness | Baryon Number | Lepton Number |
| \(\bar{u}\bar{u}\bar{d}\) | \(Q=-1\) | \(S=0\) | \(B=-1\) | \(L=0\) | |
| \(\bar{u}\bar{d}\bar{d}\) | \(Q=0\) | \(S=0\) | \(B=-1\) | \(L=0\) | |
| Fundamental | \(Q=+1\) | \(S=0\) | \(B=0\) | \(L=-1\) | |
| Fundamental | \(Q=0\) | \(S=0\) | \(B=0\) | \(L=-1\) |