Abstract
The NA48/2 experiment at CERN collected, between 2003 and 2004, 1.69×107 fully reconstructed π0→γe+e- in the kinematic range mee>10 MeV/c2, with a negligible background contamination. The sample is analysed to search for the presence of dark photons (A′) via the decay chain π0→γA′, A′→e+e-. No signal has been observed, and the exclusion limits on space of the dark photon mass mA′ and the mixing parameter 2 are reported.
Abstract
The NA48/2 experiment at CERN collected, between 2003 and 2004, 1.69×107 fully reconstructed π0→γe+e- in the kinematic range mee>10 MeV/c2, with a negligible background contamination. The sample is analysed to search for the presence of dark photons (A′) via the decay chain π0→γA′, A′→e+e-. No signal has been observed, and the exclusion limits on space of the dark photon mass mA′ and the mixing parameter 2 are reported.