Is there an eta-3He quasi--bound state ?

C. Wilkin; M. Buescher; D. Chiladze; S. Dymov; C. Hanhart; M. Hartmann; V. Hejny; A. Kacharava; I. Keshelashvili; A. Khoukaz; Y. Maeda; T. Mersmann; M. Mielke; S. Mikirtychiants; M. Papenbrock; F. Rathmann; T. Rausmann; R. Schleichert; H. Stroeher; A. Taeschner; Yu. Valdau; A. Wronska

doi:10.1016/j.physletb.2007.08.041

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arXiv · 0707.1489

Is there an eta-3He quasi--bound state ?

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Abstract

The observed variation of the total cross section for the dp -> 3He eta reaction near threshold means that the magnitude of the s--wave amplitude falls very rapidly with the eta centre--of--mass momentum. It is shown here that recent measurements of the momentum dependence of the angular distribution imply a strong variation also in the phase of this amplitude. Such a behaviour is that expected from a quasi--bound or virtual eta-3He state. The interpretation can be investigated further through measurements of the deuteron or proton analysing powers and/or spin--correlations.

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C. Wilkin, M. Buescher, D. Chiladze, S. Dymov, C. Hanhart, M. Hartmann, V. Hejny, A. Kacharava, I. Keshelashvili, A. Khoukaz, Y. Maeda, T. Mersmann, M. Mielke, S. Mikirtychiants, M. Papenbrock, F. Rathmann, T. Rausmann, R. Schleichert, H. Stroeher, A. Taeschner, Yu. Valdau, A. Wronska. 2007-07-10. Is there an eta-3He quasi--bound state ?. https://doi.org/10.1016/j.physletb.2007.08.041

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