- Hadrons are a group of subatomic particles that are made up of quarks
- These may be either a:
- Baryon (3 quarks)
- Meson (quark and anti-quark pair)
Hadrons may be either a baryon or a meson
- Quarks have never been discovered on their own, always in pairs or groups of three
- Anti-hadrons can be either
- Anti-baryons (3 anti-quarks)
- Anti-meson (quark and anti-quark pair)
Anti-hadrons may be either an anti-baryon or an anti-meson
- Note that all baryons or mesons have integer (whole number) charges eg. +1e, -2e etc.
- This means quarks in a baryon are either all quarks or all anti-quarks. Combination of quarks and anti-quarks don’t exist in a baryon
- The anti-particle of a meson is still a quark-antiquark pair. The difference being the quark becomes the anti-quark and vice versa
The baryon Δ++ was discovered in a particle accelerator using accelerated positive pions on hydrogen targets.Which of the following is the quark combination of this particle?
Remembering quark combinations is useful for the exam. However, as long as you can remember the charges for each quark, it is possible to figure out the combination by making sure the combination of quarks add up to the charge of the particle (just like in the worked example)