PHYSICS · Multi-part · Fermi University Physics · Particle Physics & Quantum Fields · Symmetry, groups and the quark model · Electroweak theory and the Standard Model
Particle Physics, Ch The Standard Model as a table you can predict from
Problem
The Ω− baryon has quark content sss, mass 1672.45MeV/c2, baryon number B=1, strangeness S=−3 and spin J=3/2. Two candidate final states are considered: ΛK−: Λ mass 1115.68MeV/c2, S=−1; K− mass 493.68MeV/c2, S=−1. Ξ0π−: Ξ0 mass 1314.86MeV/c2, S=−2; π− mass 139.57MeV/c2, S=0.
((a)) Check charge, baryon number, strangeness and mass for both channels, and state which interaction and quark-level vertex is needed for each.
((b)) Predict the order-of-magnitude lifetime band for the Ω−, and state which previously met particle lifetimes it should be comparable to.
((c)) CPT invariance predicts τ(Ωˉ+)=τ(Ω−). Given the measured values τ(Ω−)=8.21×10−11s and τ(Ωˉ+)=8.20×10−11s, state whether this is consistent with CPT.