Few-Body Systems

, Volume 55, Issue 8–10, pp 795–799 | Cite as

Search for η-Mesic 4He with WASA-at-COSY

  • W. Krzemien
  • P. Moskal
  • M. Skurzok
Open Access


An exclusive measurement of the excitation functions for the dd3Hep π and dd3Hen π 03Hen γ γ reactions was performed at the Cooler Synchrotron COSY-Jülich with the WASA-at-COSY detection system. The data were collected in two dedicated experiments in 2008 and in 2010. The experimental method and the current status of the analysis are presented.


Excitation Function Gamma Quantum Black Vertical Line Bound State Formation Exclusive Measurement 
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© The Author(s) 2014

Open AccessThis article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.

Authors and Affiliations

  1. 1.M. Smoluchowski Institute of PhysicsJagiellonian UniversityKrakówPoland
  2. 2.IKP, Forschungszentrum JülichJülichGermany

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