Speaker
Jose R. Pelaez
Description
In ExcitedQCD2014, we presented a dispersive method to calculate Regge trajectories from their associated poles in elastic pion-pion scattering, which allowed to identify the rho(770) as an ordinary meson and the f0(500) as a non-ordinary one. Here we first present a dispersive treatment with more subtractions that confirms these results. In addition, extend this method to elastic or quasi-elastic resonances appearing in pion-pion, kaon-kaon, kaon-pion and K*-pion scattering. In this way the f2(1270), f2'(1525), K*(892), K1(1410) and K0*(1430) resonances are identified as ordinary mesons.
Finally, we identify the controversial kappa or K0*(800) scalar resonance as a non-ordinary meson whose Regge trajectory is not linear and bears a striking similarity to that of the f0(500) and, at low energies, to a Regge trajectory of a Yukawa potential, whose parameters can be estimated.
Author
Co-author
Arkaitz Rodas Bilbao
(Universidad Complutense de Madrid)