Search for production of an invisible dark photon in ${\pi }^0$ decays

Abstract

The results of a search for ${\pi }^0$ decays to a photon and an invisible massive dark photon at the NA62 experiment at the CERN SPS are reported. From a total of $4.12\times 10^8$ tagged ${\pi }^0$ mesons, no signal is observed. Assuming a kinetic-mixing interaction, limits are set on the dark photon coupling to the ordinary photon as a function of the dark photon mass, improving on previous searches in the mass range 60--110 MeV/$c^2$. The present results are interpreted in terms of an upper limit of the branching ratio of the electro-weak decay ${\pi }^0\to \gamma \nu \overline{\nu }$, improving the current limit by more than three orders of magnitude.

References in corpus (3)

• Secluded U(1) below the weak scale
• New determination of the fine structure constant and test of the quantum electrodynamics
• U-boson production in e+e- annihilations, psi and Upsilon decays, and Light Dark Matter

Cited by in corpus (1)

• Experimental summary: QCD session of the 54th Rencontres de Moriond (Moriond QCD 2019)