Determine the charge conjugation, the lowest value of the orbital momentum and the isospin of the 2π systems in the decays 

(a) η → π⁺ π^- γ, 

(b) ω → π⁺ π^- γ and 

(c) ρ⁰ → π⁺ π^- γ. State also the ΔI in the decay. 

(d) State whether the following decays are allowed or forbidden and why: η → π⁰ π⁰ γ, ω → π⁰ π⁰ γ, ρ⁰ → π⁰ π⁰ γ.