Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

Area of Science:

• Physics
• Astrophysics
• Particle Physics

Background:

• The nature of dark matter remains one of the most significant unsolved problems in physics.
• Direct detection experiments aim to observe the faint interactions between dark matter particles and ordinary matter.

Purpose of the Study:

• To establish new limits on spin-independent dark matter-nucleon interactions.
• To explore the potential of athermal phonon detectors for future dark matter searches.

Main Methods:

• Utilized a 10.6 g silicon athermal phonon detector with an eV-scale energy resolution.
• Performed an exclusion analysis using a raw exposure of 9.9 g·d acquired at an above-ground facility.

Main Results:

• Achieved the most stringent dark matter-nucleon scattering cross-section limits for a cryogenic detector in the mass range of 93–140 MeV/c².
• Demonstrated eV-scale energy resolution, crucial for detecting low-energy nuclear recoils.

Conclusions:

• The results significantly constrain dark matter models within this mass range.
• Athermal phonon sensors show great promise for advancing direct dark matter detection sensitivity.