Search for a dark photon in the ${\pi }^0\to e^{+}{e}^{-}\gamma$ decay

COSY Collaboration, P. Adlarson, W. Augustyniak +113

The presently world largest data sample of pi0 --> gamma e+e- decays containing nearly 5E5 events was collected using the WASA detector at COSY. A search for a dark photon U produc…