https://doi.org/10.1051/epjconf/20123702003
Search for η-mesic Helium with the WASA-at-COSY detector
1 Institute of Physics, Jagiellonian University, Cracow, Poland
2 Institut fur Kernphysik (IKP) and Jülich Center for Hadron Physics (JCHP), Forschungszentrum Jülich, Germany
a e-mail: wojciech.krzemien@if.uj.edu.pl
A search for the 4He − η bound state via exclusive measurement of the excitation function for the dd → 3Hepπ− reaction, was performed at the Cooler Synchrotron COSY-Jülich with the WASA-at-COSY detection system. The data were taken during a slow acceleration of the beam from 2.185GeV/c to 2.400GeV/c crossing the kinematic threshold for the η production in the dd → 4He η reaction at 2.336 GeV/c. The corresponding excess energy in the 4He − η system varied from −51.4 MeV to 22 MeV. The shape of the excitation function for the dd → 3Hepπ− was examined. No signal of the 4He − η bound state was observed in the excitation function.
© Owned by the authors, published by EDP Sciences, 2012
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.