Mixing of the f(0) and a(0) scalar mesons in threshold photoproduction - art. no. 064601

We examine the photoproduction of the light scalar mesons f(0)-a(0)(980) wi th emphasis on isospin-violating f(0) and a(0) mixing due to the mass diffe rence between neutral and charged kaons. General forms for the invariant am plitude for scalar meson photoproduction are derived, which yield expressio ns for the invariant mass distribution of the final meson pairs. A final st ate interaction form factor is obtained which incorporates f(0) and a(0) me sons, K(K) over bar threshold effects, and f(0)-a(0) mixing. This form fact or is applied to predict the effective mass distribution of the pi pi and K (K) over bar pairs in the vicinity of the K(K) over bar threshold. An estim ate of the role of isospin mixing near threshold is provided. The potential role of polarized photons and protons is also discussed.