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arXiv · hep-ex/0409048

New results on the pd --> 3He eta production near threshold

Abstract

Measurements on the eta meson production in proton-deuteron collisions have been performed using the COSY-11 facility at COSY Juelich. Here we present preliminary results on total and differential cross sections for the pd --> 3He eta reaction at five excess energies between Q = 5.1 and Q = 40.6 MeV. The obtained angular distributions for the emitted eta mesons in the center of mass system expose a transition from an almost isotropic emission to a highly anisotropic distribution. The extracted total cross sections support a strong eta-3He final state interaction and will be compared with model predictions.

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H. -H. Adam, A. Khoukaz, N. Lang, T. Lister, R. Santo, S. Steltenkamp, R. Czyzykiewicz, M. Janusz, L. Jarczyk, B. Kamys, P. Moskal, C. Piskor-Ignatowicz, J. Przerwa, J. Smyrski, D. Grzonka, K. Kilian, W. Oelert, T. Sefzick, P. Winter, M. Wolke, P. Wuestner, A. Budzanowski, T. Rozek, M. Siemaszko, W. Zipper. 2004-09-22. New results on the pd --> 3He eta production near threshold. https://doi.org/10.1142/s0217751x05022032

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