Characterization of Magnetic Sensors for MAGNETO Dark Matter Search Experiments
POSTER
Abstract
The MAGNETO-χ experiment will search for sub-GeV dark matter using diamond/sapphire crystals and magnetic quantum sensors. Athermal phonons produced by dark matter scattering in the crystals are measured by magnetic quantum sensors capable of sub-microsecond timing resolution. This capability enables enhanced phonon pulse shape discrimination for active rejection of electron-recoil background and low energy noise. Magnetic quantum sensors utilize paramagnetic materials for phonon sensing and SQUID (Superconducting Quantum Interference Device) magnetometers for measurement of resulting magnetic flux changes. Au:Er paramagnetic alloy materials are synthesized, tested, and characterized for the MAGNETO-χ experiment. Cryogenic magnetic responses at millikelvin temperatures, response speed of the sensors, and magnetic coupling between the sensor and SQUID are demonstrated.
*This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work was supported by the Laboratory Directed Research and Development program of Lawrence Livermore National Laboratory (22-FS-011) and DOE Office of Science HEP Advanced Detector R&D program.
Presenters
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Geon-Bo Kim
- Lawrence Livermore National Laboratory