In Addition to Charge and Baryon Number, Another Conserved Quantity

question 22

Multiple Choice

In addition to charge and baryon number, another conserved quantity in particle interactions is lepton number. The six leptons have lepton number +1, and their antiparticles have lepton number −1. The lepton numbers for each generation (electron, muon, tau) are separately conserved. For example, an electron has electron-lepton number +1, while the electron antineutrino has electron-lepton number −1. What is the missing particle X in the following reaction? v_μ + → + X

• A) e⁻
• B) τ⁻
• C) μ⁻
• D) π⁻

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Definitions:

Interest Rate

The amount charged by lenders as a percentage of the principal, or the amount earned on deposits over a specified period.

Equilibrium Value

The point at which the quantity of a good or service demanded equals the quantity supplied, resulting in market stability.

Opportunity Cost

Whatever must be given up to obtain some item.

Holding Currency

The practice of keeping money in the form of cash or liquid assets as opposed to investing or depositing it.