The lifetime of the 0 is 6 x 10 - 20 s. The lifetime of the

The lifetime of the Σ⁰ is 6 x 10^-20 s. The lifetime of the Σ⁺ is 0.8 x 10^-10 s and that of the Σ^- is 1.48 x 10^-10 s, nearly twice as long. How can these differences in lifetimes between members of the same isospin multiplet be explained?