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arXiv · 1711.01480

Photo- and Electro-excitation of Bound Neutrons and Protons

Satoshi X. Nakamura
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Abstract

Data for pion photo-productions off the neutron ($γn\to πN$) have been primarily extracted from deuteron-target data ($γd\to πNN$) by applying kinematical cuts thereby isolating the quasi-free samples. We critically examine if the neutron-target data obtained through this conventional procedure can be contaminated by final state interactions (FSI) and/or the kinematical cuts. The analysis is conducted with a theoretical model for $γd\to πNN$ that takes account of the impulse mechanisms supplemented by the $NN$ and $πN$ rescattering mechanisms. We show that the FSI effects still visibly remain in the extracted $γ$`$n$'$\toπN$ unpolarized cross sections and polarization asymmetries $E$ even after the kinematical cuts are applied. We also find the FSI effects on $γ$`$n$'$\toπ^0n$ can be somewhat different from those on $γ$`$p$'$\toπ^0p$.

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Satoshi X. Nakamura. 2018-05-25. Photo- and Electro-excitation of Bound Neutrons and Protons. https://doi.org/10.1007/s00601-018-1404-9

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