Polarized single-pion photoproduction: Test for various quark models

The multipole analysis of resonance photocouplings of Babcock and Rosner is extended to the case of single-pion photoproduction by polarized photons. The various polarized cross sections $d{\sigma }_{\parallel }\left(n{\pi }^{+}\right)$, $d{\sigma }_{\parallel }\left(p{\pi }^0\right)$, $d{\sigma }_{\perp }\left(n{\pi }^{+}\right)$, and $d{\sigma }_{\perp }\left(p{\pi }^0\right)$ are well reproduced. The present analysis is exploited for discriminating different models which predict photocouplings of nonstrange baryon resonances. Data is found to strongly favor a negative relative sign for $P$- and $F$-wave pionic decays in accordance with the findings of Babcock and Rosner.