Double Polarization Observables Research Articles

Survey on polarization observables in deuteron photodisintegration below pion-production threshold

Polarization observables of deuteron photodisintegration with polarized photons and oriented deuterons are systematically investigated below π-production threshold with respect to their sensitivity to subnuclear degrees of freedom and relativistic effects, to the different electric and magnetic multipole contributions, and to various realistic potential models. In particular, a complete survey on all single- and double-polarization observables like beam and target asymmetries of the differential cross section, nucleon polarization and proton-neutron spin correlation is given.

Kaon photoproduction: Data consistency, coupling constants, and polarization observables.

The process \ensuremath{\gamma}p\ensuremath{\rightarrow}${\mathit{K}}^{+}$\ensuremath{\Lambda} is studied in a phenomenological approach. A thorough analysis of the existing differential cross section data up to 1.4 GeV, taking into account the systematic uncertainties, shows the Orsay data to be internally inconsistent. Removing this data set from the data base results in a rather simple reaction mechanism with the extracted main kaon-hyperon-nucleon coupling constants in agreement with the SU(3) predictions. Employing a diagrammatic model, the differential and total cross section, \ensuremath{\Lambda}-polarization, and polarized target data are well reproduced. Predictions for other single and double polarization observables and suggestions for new measurements are presented. Applying crossing symmetry, the reaction is related to the radiative ${\mathit{K}}^{\mathrm{\ensuremath{-}}}$ capture process, and a comparison with the measured branching ratio is made.

Polarization in inclusive reactions

A formalism for discussing the spin dependence of inclusive reactions is presented. The role of various constraints following from conservation of parity and angular momentum conservation is discussed. Expressions for specific single and double polarization observables are presented. Predictions of the triple-Regge model for these observables are given.