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:

Stepmother Family

A family structure that includes a stepmother, which means a woman who is married to one's father after the divorce or death of one's biological mother.

Lesbian Stepmother

A woman who is in a same-sex relationship with one biological parent of a child, and who may take on parental roles without being a biological mother.

Biological Mother

The woman who contributes half of the genetic material to, and carries the pregnancy of, a child.

Mothering Tasks

The activities and responsibilities involved in caring for and raising children, traditionally associated with maternal roles.