A Search for Sterile Neutrino Dark Matter

Executive Summary

We propose to conduct the world’s most sensitive search for kiloelectron volt sterile neutrino dark matter by implanting radioactive beryllium-7 nuclei into superconducting radiation detectors and measuring the recoil energy of the lithium-7 daughter nucleus with high accuracy. If successful, this innovative method could increase detection sensitivity three to four times more than competing approaches, significantly impacting the fields of particle physics and cosmology, as well as national missions in nuclear security.

Publications, Presentations, and Patents

Friedrich, Stephan, Geon-Bo Kim, Connor Bray, Robin Cantor, Jens Dilling, Spencer Fretwell, J. Ad Hall, Annika Lennarz, Vincenzo Lordi, Peter Machule, David McKeen, Xavier Mougeot, Francisco Ponce, Chris Ruiz, Amit Samanta, William K. Warburton, Kyle G. Leach, “Limits on the Existence of sub-MeV Sterile Neutrinos from the Decay of ⁷Be in Superconducting Quantum Sensors,” Phys. Rev. Lett. 126, 021803 (2021); doi.org/10.1103/PhysRevLett.126.021803.

Fretwell, Spencer, Kyle G. Leach, Connor Bray, Geon-Bo Kim, Jens Dilling, Annika Lennarz, Xavier Mougeot, Francisco Ponce, Chris Ruiz, Joshua Stackhouse, Stephan Friedrich, “Direct Measurement of the ⁷Be L/K Capture Ratio in Ta-Based Superconducting Tunnel Junctions,” Phys. Rev. Lett. 125, 032701 (2020); doi.org/10.1103/PhysRevLett.125.032701.

Friedrich, Stephan, Francisco Ponce, J. Ad Hall, Robin Cantor, “Non‐linearities in Superconducting Tunnel Junction Radiation Detectors and Their MCA Readout,” J. Low Temp. Phys. 200, 200 (2020); doi.org/10.1007/s10909-020-02360-2.