Chiral perturbation theory and the f(2)(1270) resonance

Abstract

Within chiral perturbation theory, we study elastic pion scattering in the I=0,J=2, channel, whose main features are the f(1270) resonance and the vanishing of the lowest order. By means of a chiral model that includes an explicit resonance coupled to pions, we describe the data and calculate the resonance contribution to the O(p(4)) and O(p(6)) chiral parameters. We also generalize the inverse amplitude method to higher orders, which allows us to study channels with vanishing lowest order. In particular, we apply it to the I=0,J=2 case, finding a good description of the f(2)(1270) resonance, as a pole in the second Riemann sheet.