Using the pole approach we determine the mass and width of the f 0 (980), in particular we analyze the possibility that two nearby poles are associated to it. We restrict our analysis to a neighborhood of the resonance, using ππ data for the phase shift and inelasticity, and the invariant mass spectrum of the J/ψ → φππ, φKK decays. The formalism we use is based on unitarity and a generalized version of the Breit-Wigner parameterization. We find that a single pole describes the f 0 (980), the precise position depending upon the ππ data used (see Eq. (19) of the main text). As a byproduct, values for the g f 0 ππ and g f 0 KK coupling constants are obtained.

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