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Experimental study of the eta-meson interaction with two-nucleons

P. Moskal·H. -H. Adam·A. Budzanowski·R. Czyzykiewicz·D. Grzonka·M. Janusz·L. Jarczyk·B. Kamys·A. Khoukaz·K. Kilian·P. Kowina·N. Lang·T. Lister·W. Oelert·T. Rozek·R. Santo·G. Schepers·T. Sefzick·M. Siemaszko·J. Smyrski·S. Steltenkamp·A. Strzalkowski·P. Winter·M. Wolke·P. Wustner·W. Zipper
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Abstract

By means of the COSY-11 detection system, using a stochastically cooled proton beam of the cooler synchrotron COSY and a hydrogen cluster target, we have performed a high statistics measurement of the pp --> pp eta reaction at an excess energy of Q = 15.5 MeV. The experiment was based on the four-momentum determination of both outgoing protons. This permits to identify pp --> pp eta events and to derive the complete kinematical information of the eta-p-p-system allowing for subsequent investigations of the eta-p interaction. The observed spectrum of the invariant mass of the proton-proton system deviates strongly from the phase-space distribution revealing the influence of the final-state-interaction among the outgoing particles or nontrivial features of the primary production mechanism.

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P. Moskal, H. -H. Adam, A. Budzanowski, R. Czyzykiewicz, D. Grzonka, M. Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, K. Kilian, P. Kowina, N. Lang, T. Lister, W. Oelert, T. Rozek, R. Santo, G. Schepers, T. Sefzick, M. Siemaszko, J. Smyrski, S. Steltenkamp, A. Strzalkowski, P. Winter, M. Wolke, P. Wustner, W. Zipper. 2002-08-02. Experimental study of the eta-meson interaction with two-nucleons. https://doi.org/10.1142/9789812791351_0043

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