Search for dark photons from supersymmetric hidden valleys

TL;DR

This paper reports a search for dark photons produced in supersymmetric cascade decays at the D0 experiment, focusing on a novel final state with a photon, close leptons, and missing energy, but finds no evidence and sets limits.

Contribution

It introduces a new search channel for dark photons involving supersymmetric cascades and a unique final state, expanding experimental exploration of hidden sector particles.

Findings

No evidence for dark photon production was observed.

Set upper limits on dark photon production cross-section.

Constrained parameter space of supersymmetric models with hidden sectors.

Abstract

We search for a new light gauge boson, a dark photon, with the D0 experiment. In the model we consider, supersymmetric partners are pair produced and cascade to lightest neutralinos that can decay into the hidden sector state plus either a photon or a dark photon. The dark photon decays through its mixing with a photon into fermion pairs. We therefore investigate a previously unexplored final state that contains a photon, two spatially close leptons, and large missing transverse energy. We do not observe any evidence for dark photons and set a limit on their production.