Question

Which of the following hyperon decays are allowed in lowest order weak interactions? 

(a) E⁰ → Σ⁻ + e⁺ + νe 

(b) E⁰ → p + π⁻ + π₀ 

(c) Ω⁻ → E⁰ + e⁻ + bar νe 

(d) Ω− → E⁻ + π⁺ + π⁻

Answer 1

Decay

(a) is forbidden by the ΔS = ΔQ rule for the semi – leptonic decays and 

(b) is forbidden by the ΔS = 0, ±1 rule for the hadronic weak decays. 

(c) and (d) are allowed and both have been experimentally observed.