f1(1285) Decays into a0(980)π0, f0(980)π0 and Isospin Breaking

We evaluate the decay width for the processes f(1)(1285) -> pi(0)a(0)(980) and f(1)(1285) -> pi(0)f(0)(980) taking into account that all three resonances are dynamically generated from the meson-meson interaction, the f(1)(1285) from K*(K) over bar + c.c and the a(0)(980), f(0)(980) from pi eta, K (K) over bar and pi pi, K (K) over bar respectively. We use a triangular mechanism similar to that of the eta(1405) -> pi pi eta, which provides a decay width for f(1)(1285) -> pi(0)a(0)(980) with a branching fraction of the order of 30%, in agreement with experiment. At the same time we evaluate the decay width for the isospin forbidden f(1)(1285) -> pi(0)f(0)(980), which appears when we consider different masses for the charged and neutral kaons, and show that it is much more suppressed than in the eta(1405) -> pi pi eta case, but gives rise to a narrow shape of the pi(+)pi(-) distribution similar to the one found in the eta(1405) -> pi pi eta decay.