Meson phenomenology

Abstract

A phenomenological investigation of soft mesonzeros is performed. Our motivation comes from the suggestion by Lovelace of a connection between Chlral Symmetry and the Dual Resonance Model. The low energy theorems relating to the particular processes with which we are concerned are discussed in detail in chapter two. We find, in chapter three, for the Pi-Pi interaction, that the experimental phase shift data, when taken in conjunction with rigorous crossing sum rules, demand the soft meson zeros. In chapter four the soft meson zeros in J-decay are discussed in the framework of the generalised pole model. The rate problem is re-examined and a satisfactory description of both the rate and the spectrum for the decay is obtained. Using the value of the weak 2vertex, g(M(^2)), obtained in chapter four, we discuss, in chapter five models for other kaon decays, namely kº˪→2ɤ and the magnetic dipole radiation in decay k(^±)→π(^±)πº ɤ and obtain results in agreement with experiment. In chapter six we return to the notorious problem of the zeros in η→3π. A solution is proposed based on the variation of the coefficients of the Veneziano sum as the external pseudoscalar mesons are taken off mass shell.