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arXiv · 1210.4763

Search for eta-mesic Helium with the WASA-at-COSY detector

Wojciech Krzemien·Pawel Moskal·Jerzy Smyrski·Magdalena Skurzok
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Abstract

A search for the 4He-eta bound state via exclusive measurement of the excitation function for the dd->3Heppi- reaction, was performed at the Cooler Synchrotron COSY-Juelich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185 GeV/c to 2.400 GeV/c crossing the kinematic threshold for the eta production in the dd -> 4He-eta reaction at 2.336 GeV/c. The corresponding excess energy in the 4He-eta system varied from -51.4 MeV to 22 MeV. The shape of the excitation function for the dd -> 3Heppi- was examined. No signal of the 4He-eta bound state was observed in the excitation function.

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Wojciech Krzemien, Pawel Moskal, Jerzy Smyrski, Magdalena Skurzok. 2012-10-17. Search for eta-mesic Helium with the WASA-at-COSY detector. https://doi.org/10.1051/epjconf%2F20123702003

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