Some Predictions of the Amati-Bertocchi-Fubini-Stanghellini-Tonin Multiperipheral Model

Abstract

The predictions of the Amati-Bertocchi-Fubini-Stanghellini-Tonin multiperipheral model based on pion pole dominance are calculated quantitatively and compared with experimental data, by using the Veneziano representation for the $\pi -\pi$ amplitude, with a cutoff at the mass of the $g$ resonance for the input kernel, and neglecting off-shell effects. We find ${\alpha }_P\mathrm{}\left(0\right)=0.30\mathrm{}$, ${\alpha }_{\rho }\mathrm{}\left(0\right)=0.16\mathrm{}$, an average multiplicity growing as 0.74 $\ln s$, an elasticity factor of 0.69, an average pion-pair transverse momentum equal to 0.43 $\frac{\mathrm{GeV}}{c}$, and an average invariant mass squared equal to 0.84 Ge${\mathrm{V}}^2$. The only serious discrepancies with experiment are the trajectory heights, which correspond to a kernel strength $2\frac{1}{2}-5$ times too weak. The inclusion of the high-subenergy contribution and the inclusion of off-shell effects by several methods of off-shell continuation are considered, but none is found to be satisfactory. The importance of interference terms, due to different ways of arranging the final-state particles along the multiperipheral chain, is discussed.