Speaker
Riccardo Fantechi
Description
A sample of 17 million fully reconstructed $\pi^0$ Dalitz decays produced in
charged kaon decays in flight collected by the NA48/2 experiment at CERN in
2003-04 is analysed to search for the dark photon ($A$) via the decay chain
$\pi^0 \rightarrow \gamma A$, $A \rightarrow e^+ e^-$.
No dark photon signal is observed, and the most stringent limits on the dark photon mixing parameter in the mass range 9-70 MeV are established. Limitations of the method and possible future directions are discussed.
