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Low energy scattering and photoproduction of $η$-mesons on deuterons

N. V. Shevchenko·V. B. Belyaev·S. A. Rakityansky·S. A. Sofianos·W. Sandhas
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Abstract

Photo-production of $η$-mesons and their collisions with light nuclei are studied within the Alt-Grassberger-Sandhas (AGS) formalism for different parameters of $ηN$ interaction. A three-body resonance or a quasi-bound state is found close to the $ηd$ threshold. Expected manifestation of this resonant behavior of $ηd$ elastic scattering in various processes involving $ηd$-system in their final states was found in calculations of the $γd \to ηd$ reaction in the framework of modified AGS equations. These calculations revealed peaks in the energy dependence of the total cross-section almost at the same energies as in the elastic $ηd$ scattering. Meanwhile, such peaks did not appear in the impulse approximation (i.e. when $ηd$ resonance was not taken into account). This sheds some light on the nature of the enhancement of $η$ photo-production on deuteron observed recently in the low energy experiments.

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N. V. Shevchenko, V. B. Belyaev, S. A. Rakityansky, S. A. Sofianos, W. Sandhas. 2001-05-17. Low energy scattering and photoproduction of $η$-mesons on deuterons. https://arxiv.org/abs/nucl-th/0011027

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