Search for Neutron-to-Hidden-Neutron Oscillations in an Ultracold Neutron Beam

• Published in: Physical review letters 2023-11, Vol.131 (19), p.191801-191801, Article 191801
• Main Authors: Ban, G., Chen, J., Lefort, T., Naviliat-Cuncic, O., Saenz-Arevalo, W., Chiu, P.-J., Clément, B., Larue, P., Pignol, G., Roccia, S., Guigue, M., Jenke, T., Perriolat, B., Schmidt-Wellenburg, P.
• Format: Article
• Language: English
• Subjects: Nuclear Experiment; Nuclear Theory; Physics
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.131.191801

Models that postulate the existence of hidden sectors address contemporary questions, such as the source of baryogenesis and the nature of dark matter. Neutron-to-hidden-neutron oscillations are among the possible mixing processes and have been tested with ultracold neutron storage and passing-through-wall experiments to set constraints on the oscillation period τ_{nn^{'}}. These searches probe the oscillations as a function of the mass splitting due to the neutron-hidden-neutron energy degeneracy. In this work, we present a new limit derived from neutron disappearance in ultracold neutron beam experiments. The overall limit, given by τ_{nn^{'}}>1  s  for |δm|∈[2,69]  peV(95.45%  C.L.), covers the yet unexplored intermediate mass-splitting range and contributes to the ongoing research on hidden sectors.