Search for a Narrow Resonance in e+e- to Four Lepton Final States

Abstract

Motivated by recent models proposing a hidden sector with $\sim$GeV scale force carriers, we present a search for a narrow dilepton resonance in 4 lepton final states using $536f{b}^{-1}$ collected by the BaBar detector. We search for the reaction, $e^{+}{e}^{-}\to W^{\prime }{W}^{\prime }\to (l^{+}{l}^{-})(l^{\prime +}{l}^{\prime -})$, where the leptons carry the full 4-momentum and the two dilepton pair invariant masses are equal. We do not observe a significant signal and we set 90% upper limits of $\sigma (e^{+}{e}^{-}\to W^{\prime }{W}^{\prime }\to (e^{+}{e}^{-})(e^{+}{e}^{-}))<(15-70)ab$, $\sigma (e^{+}{e}^{-}\to W^{\prime }{W}^{\prime }\to (e^{+}{e}^{-})({\mu }^{+}{\mu }^{-}))<(15-40)ab$, and $\sigma (e^{+}{e}^{-}\to W^{\prime }{W}^{\prime }\to ({\mu }^{+}{\mu }^{-})({\mu }^{+}{\mu }^{-}))<(11-17)ab$ in the $W^{\prime }$ mass range between 0.24 and 5.3GeV. Under the assumption that the $W^{\prime }$ coupling to electrons and muons is the same, we obtain a combined upper limit of $\sigma (e^{+}{e}^{-}\to W^{\prime }{W}^{\prime }\to (l^{+}{l}^{-})(l^{\prime +}{l}^{\prime -}))<(25-60)ab$. Using these limits, we constrain the product of the SM-dark sector mixing and the dark coupling constant in the case of a non-Abelian Higgsed dark sector.

submitted to Lepton-Photon 2009

References in corpus (2)

• Probing a Secluded U(1) at B-factories
• Probing Dark Forces and Light Hidden Sectors at Low-Energy e+e- Colliders