P.A. Collins

A parameter-free Reggeized absorption model for meson-baryon scattering

Abstract A Reggeized absorption model containing no free parameters to be fitted to the data being explained is applied to a wide range of meson-baryon scattering reactions. This model incorporates U(6, 6) ⊗ O(3, 1) symmetry and strong exchange degeneracy in the pole-graph amplitudes. The agreement between the theoretical predictions and the experimental data on differential cross sections, polarizations and spin density matrix elements is extremely encouraging.

A parameter-free Reggeized absorption model for Δ (1236) production in proton-proton reactions

Abstract A Reggeized absorption model containing no free parameters to be fitted by the data under consideration is applied to single and double Δ(1236) production in proton-proton reactions in the energy range 5–24 GeV/ c . Extremely favourable agreement is obtained between the theoretical predictions and the experimental data on differential cross sections and density matrix elements.

The generalized veneziano model for π−p→K0K0n

The model proposed by Petersson and Tornqvist [1] is applied to the process π−p→K0K0n at 12 GeV/c. Th results are compared with the data used by Chan et al. in an application of a double Regge model [2] to this process.

The Reggeized U(6) ⊗ U(6) ⊗ O(3) absorptive peripheral model for O−12+ → O−12+ hypercharge-exchange reactions

The O−12+ → O−12+ hypercharge-exchange reactions: π−p → KOΛ(ΣO), π−p → KOΛ, K−n → π−Λ, K−n → π−ΣO, π+p → K+Σ+ and K−p → π−Σ+ are studied within the framework of the Reggeized U(6) ⊗ U(6) ⊗ O(3) absorptive peripheral model. The differential cross-section data for π−p → KOΛ(ΣO) is used to determine the parameters for the K∗(890) and the KN(1420) exchanges. With these parameters absolute predictions are mode for the differential cross sections for the other reactions. Agreement with experiment is reasonable. The polarization parameter P(t) is presented. Good agreement is obtained for |t| < 0.3.

Regge-cut discontinuity equations and self-consistent solutions for multi-pomeron cuts

Abstract Using the results on the n -reggeon cut obtained by Gribov, Pomeranchuk and Ter-Martirosyan, we construct formal solutions for a two-particle scattering amplitude involving the exchange of a pomeron and multi-pomeron cuts.

A Veneziano model, with absorptive corrections, for higher spin production

A Veneziano model is applied to higher spin production processes in the near forward scattering region over an extended energy range, for the processes K+p to K0 Delta ++ and K+p to K*+p. Absorption corrections are included to take some account of unitarity, and the U(6,6) symmetry scheme is used to determine the coupling constants. While the results for K*+p are an improvement on previous Regge calculations, the results for K0 Delta ++ are similar and suffer from the fact that the N Delta coupling constant is too small.

The reggeized u(6) x u(6) x o(3) absorptive peripheral model for o-1/2+ ---> o-1/2+ hypercharge-exchange reactions

The O−12+ → O−12+ hypercharge-exchange reactions: π−p → KOΛ(ΣO), π−p → KOΛ, K−n → π−Λ, K−n → π−ΣO, π+p → K+Σ+ and K−p → π−Σ+ are studied within the framework of the Reggeized U(6) ⊗ U(6) ⊗ O(3) absorptive peripheral model. The differential cross-section data for π−p → KOΛ(ΣO) is used to determine the parameters for the K∗(890) and the KN(1420) exchanges. With these parameters absolute predictions are mode for the differential cross sections for the other reactions. Agreement with experiment is reasonable. The polarization parameter P(t) is presented. Good agreement is obtained for |t| < 0.3.

REGGEIZED U(6) x U(6) x O(3) ABSORPTIVE PERIPHERAL MODEL FOR O

The O−12+ → O−12+ hypercharge-exchange reactions: π−p → KOΛ(ΣO), π−p → KOΛ, K−n → π−Λ, K−n → π−ΣO, π+p → K+Σ+ and K−p → π−Σ+ are studied within the framework of the Reggeized U(6) ⊗ U(6) ⊗ O(3) absorptive peripheral model. The differential cross-section data for π−p → KOΛ(ΣO) is used to determine the parameters for the K∗(890) and the KN(1420) exchanges. With these parameters absolute predictions are mode for the differential cross sections for the other reactions. Agreement with experiment is reasonable. The polarization parameter P(t) is presented. Good agreement is obtained for |t| < 0.3.