Physics A-Level
Baryon number
What Baryon number means in Physics A-Level, as defined for AQA.
Definitions of Baryon number
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Reference: AQA
A bookkeeping property that is +1/3 for every quark and −1/3 for every antiquark, so three quarks give a baryon number of 1.
A conserved quantum number that tracks baryons, with each baryon assigned 1 and each antibaryon assigned −1.
Each quark carries baryon number ⅓ and each antiquark has baryon number −⅓.
Topics that use Baryon number
- Classification of particles (AQA A-Level)
- Quarks and antiquarks (AQA A-Level)
Related terms
- Baryons
- Mesons
- Strangeness
- Antiquarks
- Baryons and antibaryons
- Conservation laws
- Conservation laws in particle decays
- Conservation of baryon number
Using Baryon number in the exam
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