Photoproduction of K * vector mesons off nucleon is investigated within the Regge framework where the electromagnetic vertex of γK * K * fully takes into account the magnetic dipole and electric quadrupole moments of spin-1 K * vector meson. The t-channel K * (892), K(494) and κ(800) meson exchanges are considered for the analysis of the production mechanism. The experimentally observed rapid decrease of the cross sections for the γp → K * + Λ reaction beyond the resonance region is well reproduced by the dominance of the exchange of K-meson trajectory. The role of the scalar κmeson trajectory is found to be minor in both γp and γn reactions. The cross sections for the γn → K * 0 Λ reaction are predicted to be about twice those of the γp → K * + Λ reaction. The role of the K * electromagnetic multipoles and the proton anomalous magnetic moment is studied through the total and differential cross sections and spin/parity asymmetries. We suggest the measurement of the photon polarization asymmetry as a tool for identifying the role of the magnetic dipole and electric quadrupole moments of the K * vector meson.

Photoproduction of the Λ * (1520) resonance of spin-parity 3 2 − off the proton target is investigated within the Regge framework where the t-channel reggeization is applied for the K(494) + K * (892) + K * 2 (1430) exchanges in the Born amplitude. The present model is based on the two basic ingredients; the one is the minimal gauge prescription for the convergence of the reaction and the other is the role of the K * 2 crucial to be consistent with high energy data. The cross sections for the total, differential and photon polarization asymmetry are reproduced without fit parameters and compared with existing data. The LAMP2 and LEPS measurements of the angular distribution of the K − in the Λ * (1520) → K − p decay are investigated and found to be dominated by the decay of Λ * with helicity ±3/2 based on the analysis of the density matrix elements related. Detailed discussion on the density matrix elements is given to clarify the analysis of the observable. The reaction mechanism is featured by the dominance of the contact term with the K and K * 2 exchanges following in the low energy region. The K * exchange appears in minor role. At high energies beyond Eγ ≈ 5 GeV the role of K * 2 exchange leads over other exchanges in the reaction process.

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Charge exchange process π − p → π 0 n and elastic scatterings π ± p → π ± p are investigated within the Regge framework where the relativistic Born amplitude is reggeized for the t-channel meson exchange. Charge exchange cross section is featured by the single ρ exchange. Additional correction by Regge cuts, ρ-f2 and ρ-Pomeron, agree with differential cross sections and new trajectory for the ρ ′ (1450) exchange is attempted to reproduce polarization data. For the description of elastic scattering data up to pion momentum P Lab ≈ 250 GeV/c, Pomeron exchange of the Donnachie-Landshoff type is newly constructed and applied in this work. Elastic cross section data are well reproduced with the dominance of f2 and Pomeron exchanges in intermediate and high energies.Analysis of nucleon resonances is presented to test the validity of the present Regge framework below W ≤ 2 GeV.

Electroproduction of π + above the resonance region is analyzed in the Regge model for π + ρ exchanges. The importance of the roles of the pion and the proton form factors in the process is discussed in comparison with the existing models of Kaskulov and Mosel and of Vrancx and Ryckebusch. The present model with a proton form factor of a simple dipole-type is shown to yield a better description of DESY and JLab data over those models for the high Q 2 and −t region up to 5 GeV 2 .