TEST OF A RELATIVISTIC MANY-CHANNEL RESONANCE FORMULA

A relativistic many-channel resonance formula for the ρ{variant} meson, proposed recently by Ball and Parkinson, is tested on a compilation of experimental data. It is shown that the formula describes well the behaviour of the phase shift δ11 near the ρ{variant} resonance. Ball and Parkinson argue that the NN, πω and K*K channels are decisive for the dynamical origin of the ρ{variant} meson. We find that the shape of the ρ{variant} resonance in the ππ channel is given mainly by the coupling of the ρ{variant} meson to the ππ channel. However, the ππ channel alone cannot repreduce the shape satisfactorily, and it is necessary to take one or two additional channels into consideration [NN(+-), πω or K*K]. we find the ρ{variant} meson parameters Mρ{variant}- = 767.6 ± 1.7 MeV, Γ0 = 152±18 MeV, in agreement with our previous results. © 1969.