Meson Photo- and Electroproduction
Abstract
Description
Photo- and electroproduction of pions and eta-mesons is studied on the nucleon. The formalism of such reactions is presented including polarization degrees of freedom and theoretical approaches are discussed. In particular, the threshold and $Δ$-resonance region of pion photoproduction is considered and recent developments on low energy theorems (LET) and the E2/C2 quadrupole excitation of the $Δ$ are presented. For eta photoproduction we show our calculations for the threshold region of the new Mainz experiment and demonstrate the sensitivity of this reaction to the elementary $ηNN$ coupling and the resonance parameters of the $S_{11}(1535)$. In nuclear applications we point out the importance and advantage of light nuclei as $d$, $^3H$, $^3He$ and $^4He$ for the isospin structure of the reactions as well as for medium effects of the nucleon resonances.
40 pages, 22 figures (available from the author) Lecture notes given at the II TAPS workshop, Alicante 1993 Mainz preprint MKPH-T-93-16
40 pages, 22 figures (available from the author) Lecture notes given at the II TAPS workshop, Alicante 1993 Mainz preprint MKPH-T-93-16