Regge-Pole Phenomenology and Forward Dispersion Relations

Six sum rules derived from forward dispersion relations are used to improve the analysis of the forward $\pi -N$, $K-N$, and $\overline{K}-N$ scattering amplitudes in terms of Regge poles. A numerical analysis shows that these sum rules are not in disagreement with the available data regarding total cross sections and forward charge-exchange differential cross sections. It is also shown that they are rather effective in improving the accuracy of the determination of the Regge-pole parameters. The position of the second Pomeranchuk pole and the possible existence of a third vacuum singularity are discussed.