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arXiv · 1905.01912

Constraints on the Dark Matter Interpretation $n \rightarrow \chi + e^+ e^-$ of the Neutron Decay Anomaly with the PERKEO II experiment

M. Klopf·E. Jericha·B. Märkisch·H. Saul·T. Soldner·H. Abele
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Abstract

Discrepancies from in-beam and in-bottle type experiments measuring the neutron lifetime are on the 4$\sigma$ standard deviation level. In a recent publication Fornal and Grinstein proposed that the puzzle could be solved if the neutron would decay on the one percent level via a dark decay mode, one possible branch being $n \rightarrow \chi + e^+ e^-$. With data from the \perkeoII experiment we set limits on the branching fraction and exclude a one percent contribution for $95\,\%$ of the allowed mass range for the dark matter particle.

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M. Klopf, E. Jericha, B. Märkisch, H. Saul, T. Soldner, H. Abele. 2019-05-06. Constraints on the Dark Matter Interpretation $n \rightarrow \chi + e^+ e^-$ of the Neutron Decay Anomaly with the PERKEO II experiment. https://doi.org/10.1103/physrevlett.122.222503

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