Search for a dark photon at BABAR

TL;DR

This paper reports a search for dark photons decaying into electron or muon pairs using BABAR data, setting new upper limits on their mixing parameters and constraining dark sector theories.

Contribution

First search for dark photons in BABAR data focusing on decays to leptons, providing tighter constraints on dark sector models.

Findings

No evidence for dark photons was found.

Upper limits on dark photon mixing were established.

Constraints on dark sector theories were improved.

Abstract

We present the results of a search for a dark photon decaying to $e^+e^-$ or $\mu^+\mu^-$ in the \babar\ detector. We find no evidence for such a dark photon and set upper limits on the dark mixing as a function mass, tightening the constraints on the parameter space of several dark sector theories.