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Three-Body Analysis of Incoherent Photoproduction of $η$ Mesons on the Deuteron near Threshold

A. Fix·H. Arenhoevel
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Abstract

The importance of three-body dynamics in the $ηnp$ system in elastic and inelastic $η$-deuteron scattering as well as coherent and incoherent $η$ photoproduction on the deuteron in the energy region from threshold up to 30 MeV above has been investigated. It is shown that a restriction to first order rescattering with respect to the $NN$- and $ηN$-final state interactions, i.e., restriction to rescattering in the two-body subsystems, does not give a sufficiently accurate approximation to the s-wave reaction amplitude and that higher order terms, as described by the three-body dynamics give very substantial contributions.

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A. Fix, H. Arenhoevel. 2002-09-26. Three-Body Analysis of Incoherent Photoproduction of $η$ Mesons on the Deuteron near Threshold. https://arxiv.org/abs/nucl-th/0209085

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