Extraction of $\gamma n\to \pi N$ observables from deuteron-target data

Abstract

An examination is conducted on a commonly used procedure for extracting (un)polarized $\gamma n\to {\pi }^{-}p$ and $\gamma n\to {\pi }^{0}n$ observables from $d(\gamma ,{\pi }^{-})pp$ and $d(\gamma ,{\pi }^0)pn$ data, using a model that consists of the impulse term and the final-state interaction (FSI) terms due to nucleon- and pion-exchange. Recent experimental and theoretical analyses used an extraction method that does not impose a cut on the final $\pi N$ invariant mass $W$. I demonstrate that the use of this method can result in the $\gamma n\to \pi N$ observables that are seriously distorted by the nucleon Fermi motion, and that one can efficiently avoid this problem by imposing a cut on $W$. It is also shown that the use of kinematical cuts of recent experimental analyses can still leave in the selected samples substantial FSI effects that must be corrected in extracting the $\gamma n\to \pi N$ cross sections. In terms of the nucleon- and pion-exchange mechanisms, I give the first qualitative explanation of the FSI corrections, obtained in a recent MAMI experiment, for extracting $\gamma n\to {\pi }^{0}n$ cross sections.

6 pages, 5 figures. arXiv admin note: text overlap with arXiv:1804.04757; published version after minor modifications

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Cited by in corpus (6)

• Electroweak pion-production on nuclei within the extended factorization scheme
• Impact of final state interactions on neutrino-nucleon pion production cross sections extracted from neutrino-deuteron reaction data
• On the Photoproduction Reactions $\gamma d\to \pi NN$
• A three-body calculation of incoherent ${\pi }^0$ photoproduction on a deuteron
• Dynamical coupled-channels approach to electroweak meson productions on nucleon and deuteron
• $\eta$ photoproduction off the deuteron and low-energy $\eta$-nucleon interaction