Search for the eta-mesic 4He with WASA-at-COSY detector
Creators: name: Adlarson, P.
name: Augustyniak, W.
name: Bardan, W.
name: Bashkanov, M.
name: Bednarski, T.
name: Bergmann, F. S.
name: Berlowski, M.
name: Bhatt, H.
name: Buescher, M.
name: Calen, H.
name: Clement, H.
name: Coderre, D.
name: Czerwinski, E.
name: Demmich, K.
name: Doroshkevich, E.
name: Engels, R.
name: Erven, W.
name: Eyrich, W.
name: Fedorets, P.
name: Foehl, K.
name: Fransson, K.
name: Goldenbaum, F.
name: Goslawski, P.
name: Goswami, A.
name: Grigoryev, K.
name: Gullstroem, C. -O.
name: Hauenstein, F.
name: Heijkenskjoeld, L.
name: Hejny, V.
name: Hinterberger, F.
name: Hodana, M.
name: Hoeistad, B.
name: Jany, A.
name: Jany, B. R.
name: Jarczyk, L.
name: Johansson, T.
name: Kamys, B.
name: Kemmerling, G.
name: Khan, F. A.
name: Khoukaz, A.
name: Kistryn, S.
name: Klaja, J.
name: Kleines, H.
name: Klos, B.
name: Krapp, M.
name: Krzemien, W.
name: Kulessa, P.
name: Kupsc, A.
name: Lalwani, K.
name: Lersch, D.
name: Li, L.
name: Lorentz, B.
name: Magiera, A.
name: Maier, R.
name: Marciniewski, P.
name: Marianski, B.
name: Mikirtychiants, M.
name: Morsch, H. -P.
name: Moskal, P.
name: Nandi, B. K.
name: Niedzwiecki, S.
name: Ohm, H.
name: Ozerianska, I.
name: del Rio, E. Perez
name: Plucinski, P.
name: Podkopal, P.
name: Prasuhn, D.
name: Pricking, A.
name: Pszczel, D.
name: Pysz, K.
name: Pyszniak, A.
name: Redmer, C. F.
name: Ritman, J.
name: Roy, A.
name: Rudy, Z.
name: Sawant, S.
name: Schadmand, S.
name: Schmidt, A.
name: Sefzick, T.
name: Serdyuk, V.
name: Shah, N.
name: Siemaszko, M.
name: Siudak, R.
name: Skorodko, T.
name: Skurzok, M.
name: Smyrski, J.
name: Sopov, V.
name: Stassen, R.
name: Stepaniak, J.
name: Stephan, E.
name: Sterzenbach, G.
name: Stockhorst, H.
name: Stroeher, H.
name: Szczurek, A.
name: Tolba, T.
name: Trzcinski, A.
name: Varma, R.
name: Vlasov, P.
name: Wagner, G. J.
name: Weglorz, W.
name: Wolke, M.
name: Wronska, A.
name: Wuestner, P.
name: Wurm, P.
name: Yamamoto, A.
name: Yuan, X.
name: Yurev, L.
name: Zabierowski, J.
name: Zheng, C.
name: Zielinski, M. J.
name: Zipper, W.
name: Zlomanczuk, J.
name: Zupranski, P.
name: Zurek, M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: An exclusive measurement of the excitation function for the dd-&gt;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 meson production in the dd-&gt;4He-eta reaction at 2.336 GeV/c. The corresponding excess energy with respect to the 4He-eta system varied from -51.4MeV to 22MeV. The integrated luminosity in the experiment was determined using the dd-&gt;3Hen reaction. The shape of the excitation function for the dd-&gt;3Heppi- was examined. No signal of the 4He-eta bound state was observed. An upper limit for the cross-section for the bound state formation and decay in the process dd-&gt;(4He-eta)bound-&gt;3Heppi- was determined on the 90% confidence level and it varies from 20nb to 27nb for the bound state width ranging from 5MeV to 35MeV, respectively.
description: 8 pages, 9 figures