Scalar isoscalar form factors for energies above 1 GeV

Abstract

We present a new parametrization for scattering amplitudes and form factors, which is consistent with high-accuracy dispersive representations at low energies but at the same time allows for a data description of higher mass resonances such as the f0(1500) and f0(2020). The formalism is general and thus can be applied to many decay processes. As an example we discuss the decay of $ \bar {B}_s^0 $ → J/ψππ(KK). From the amplitude fixed in a fit to the experimental data pole positions and residues are extracted via Padé approximants.