Eur. Phys. J. A (2015) 51: 48
https://doi.org/10.1140/epja/i2015-15048-5

Regular Article - Theoretical Physics

f₁(1285) decays into a₀(980)π⁰, f₀(980)π⁰ and isospin breaking

¹ Departamento de Fısica Teórica, Universidad de Valencia and IFIC, Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigación de Paterna, Aptdo. 22085, 46071, Valencia, Spain
² Instituto de Física, Universidade de São Paulo, C. P. 66318, 05389-970, São Paulo, SP, Brasil

^* e-mail: aceti@ific.uv.es

Received: 11 February 2015
Revised: 7 April 2015
Accepted: 14 April 2015
Published online: 27 April 2015

Abstract

We evaluate the decay width for the processes f ₁(1285) → π⁰ a ₀(980) and f ₁(1285) → π⁰ f ₁(980)taking into account that all three resonances are dynamically generated from the meson-meson interaction, the f ₁(1285) from and the a ₀(980), f ₀(980) from πη, and ππ, , respectively. We use a triangular mechanism similar to that of η(1405) → ππη, which provides a decay width for f ₁(1285) → π⁰ 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) → π 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 η(1405) → ππη case, but gives rise to a narrow shape of the π ⁺ π ⁻ distribution similar to the one found in the η(1405) → ππη decay.