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Coherent $η$-photoproduction on $^4$He and $^{12}$C in the near-threshold region

A. Fix·H. Arenhoevel
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Abstract

Coherent $η$ meson photoproduction on $^4$He and $^{12}$C is considered in the near-threshold region. The elementary $η$ photoproduction operator includes contributions from the $S_{11}(1535)$ and $D_{13}(1520)$ resonances as well as $t$-channel vector meson exchange and the nucleon pole terms. Due to the suppression of the dominant $S_{11}(1535)$ resonance for spin and isospin saturated nuclei, the reaction is mainly governed by $ω$ exchange. Furthermore, the influence of Fermi motion and of different prescriptions for the choice of the invariant reaction energy $W_{γN}$ in the elementary amplitude is studied.

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A. Fix, H. Arenhoevel. 1997-02-28. Coherent $η$-photoproduction on $^4$He and $^{12}$C in the near-threshold region. https://doi.org/10.1016/s0375-9474(97)00179-6

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