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تسجيل مستخدم جديدParity violating pion electroproduction off the nucleon
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Parity violating (PV) contributions due to interference between $gamma$ and $Z^0$ exchange are calculated for pion electroproduction off the nucleon. A phenomenological model with effective Lagrangians is used to determine the resulting asymmetry for the energy region between threshold and $Delta(1232)$ resonance. The $Delta$ resonance is treated as a Rarita-Schwinger field with phenomenological $N Delta$ transition currents. The background contributions are given by the usual Born terms using the pseudovector $pi N$ Lagrangian. Numerical results for the asymmetry are presented.
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