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Updated: Sep 29, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
X17 Discovery Potential in the γN→e^{+}e^{-}N Process at Electron Scattering Facilities
Johannes Backens1, Marc Vanderhaeghen1
1Institut für Kernphysik and PRISMA+ Cluster of Excellence, Johannes Gutenberg-Universität, D-55099 Mainz, Germany.
Abstract:
We propose a direct search for the X17 particle, which was conjectured to explain the ATOMKI ^{8}Be and ^{4}He anomalies, through the dilepton photoproduction process on a nucleon in the photon energy range below or around the pion production threshold. For the scenarios of either pseudoscalar, vector, or axial-vector quantum numbers of the conjectured X17, we use existing constraints to estimate the X17 signal process. For dilepton invariant mass resolutions which have been achieved in previous experiments, a signal-to-background ratio of up to an order of magnitude is found for a neutron target, and, in particular, for the pseudoscalar and vector X17 scenarios.
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