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Meson Photo- and Electroproduction

Lothar Tiator
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Abstract

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.

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Lothar Tiator. 1994-01-19. Meson Photo- and Electroproduction. https://arxiv.org/abs/nucl-th/9401014

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