Improved Limits on n → n' Transformation from the Spallation Neutron Source and Preliminary Results from the High Flux Isotope Reactor

ORAL

Abstract

The known-dominance of matter over antimatter in the observed universe cannot be explained by the Standard Model of Particle physics. The explanation of this imbalance requires the violation of Baryon number Β (the total number of protons and neutrons in nature). Conversions between neutrons n and a Dark Matter mirror neutron n' have been proposed as such a mechanism for this Β violation. In the special case that there is a small mass △m between the n and n' states, oscillations can be enhanced by compensating for the △m with a magnetic field. Utilizing a regeneration (n → n' → n) method, a search for such oscillations was performed at the Spallation Neutron Source by placing a thin cadmium wafer inside a 5 T superconducting magnet. We observed no regenerated neutrons above the background. In our new paper, improved limits for regeneration transformation have been set in terms of the model parameters. As well, a preliminary result of an improved experiment performed at the High Flux Isotope Reactor earlier this year are discussed.

*This research was sponsored by the U.S. Department of Energy (DOE), Office of Science, Office of Nuclear Physics [contract DE-AC05-00OR22725], by the Laboratory Directed Research and Development Program [project 8215] of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. DOE, and in part by the U.S. DOE, Office of Science, Office of Work- force Development for Teachers and Scientists (WDTS) under the Science Undergraduate Laboratory Internship program. The research of the University of Tennessee, Knoxville group was partially supported by US DOE Grant DE-SC0023149. This research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory.

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Presenters

  • Cary Rock

    • University of Tennessee

Authors

  • Cary Rock

    • University of Tennessee

  • Frank M Gonzalez

    • ORNL

  • Leah J Broussard

    • Oak Ridge National Lab

  • Lisa DeBeer-Schmitt

    • ORNL

  • Michael Fitzsimmons

    • ORNL

  • Matthew Frost

    • Oak Ridge National Lab

  • Lawrence H Heilbronn

    • University of Tennessee

  • Erik B Iverson

    • Oak Ridge National Lab

  • Yuri Kamyshkov

    • University of Tennessee

  • Michael Kline

    • Battelle

  • David Milstead

    • Stockholm University

  • Seppo Pentilla

    • Oak Ridge National Lab

  • Devyn Powers

    • University of Tennessee

  • James Rogers

    • University of Tennessee

  • Valentina Santoro

    • Lund University

  • Alexander Saunders

    • Oak Ridge National Lab

  • Shaun G Vavra

    • University of Tennessee