The phi--> pi^+ pi^-and phi radiative decays within a chiral unitary approach (original) (raw)

We report on recent results on the decay of the φ into π + π − and φ radiative decays into π 0 π 0 γ and π 0 ηγ, which require the consideration of the final state interaction of a pair of mesons in a region inaccessible to Chiral Perturbation Theory. By using nonperturbative chiral unitary methods for the meson meson interaction we can obtain the corresponding decay widths and the results are compared with recent experimental data. 1 The φ → π + π − decay The φ decay into π + π − is an example of isospin violation. The φ has isospin I = 0, spin J = 1, and hence it does not couple to the π + π − system in the isospin limit, which implies the rule I + J = even. The experimental situation on this decay is rather confusing. There are two older results whose central