0000000000515161
AUTHOR
L. M. Nath
Parity-violating effects in electroproduction of theΔ(1232)by polarized electrons
Parity-violating effects in the (quasi)elastic scattering of longitudinally polarized electrons from spin-\textonehalf{} targets are discussed in the framework of the unified guage theories of weak and electromagnetic interactions. In particular, the $R\ensuremath{-}L$ asymmetry in electroproduction of the $\ensuremath{\Delta}(1232)$ is studied in considerable detail, taking into account the full spin-$\frac{3}{2}$ structure of this resonance. Our results are valid for all values of $E$ and the entire range of ${Q}^{2}$. Numerical predictions are given for the standard Weinberg-Salam model at several energies of the electron beam.
Photoproduction of pions at low energy
Presented in this paper is a field theory model for photoproduction of pions at low energy. In particular, it is shown that certain interaction terms, which were previously considered to be essential in order to explain the experimental situation corresponding to the spin-3/2 resonances, are really unnecessary and that the presence of these terms are not justifiable from the theoretical point of view. Further, the free parameters in the theory representing the off-mass-shell effects of the spin-3/2 particles are fixed on the basis of theoretical considerations.