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arXiv · 2110.06055

X17 discovery potential in the $γN \rightarrow e^+ e^- N$ process at electron scattering facilities

Johannes Backens·Marc Vanderhaeghen
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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 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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Johannes Backens, Marc Vanderhaeghen. 2021-10-12. X17 discovery potential in the $γN \rightarrow e^+ e^- N$ process at electron scattering facilities. https://doi.org/10.1103/physrevlett.128.091802

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