Speaker
Description
The SuperCDMS HVeV program is an ongoing R&D effort to develop low energy threshold detectors for low-mass (sub-GeV) dark matter searches. The program focuses on gram-scale detectors, with the joint goals of probing new parameter space, and improving our understanding of phonon dynamics and low energy backgrounds in these detectors to inform the next generation of larger scale detectors. These sensors have achieved sub-eV resolution, and by exploiting the Neganov–Trofimov–Luke (NTL) effect, single electron resolution in Si.
We present progress in two avenues of ongoing development and characterization – position-dependent mapping of phonon collection in these detectors, and implementing these detectors on a variety of substrates, with a focus on carbon-based materials. By taking advantage of a steerable cryogenic mirror system, we illuminate the backside of the detectors with sub-mm positional accuracy, enabling us to measure the response to phonons emitted from different areas of the detector surface. Using this approach, we can deduce the detector’s position-dependent phonon collection efficiency and take steps toward position reconstruction of arbitrary events within the detector. In this talk we will show our latest results characterizing these detectors with this tool.
Carbon based target materials present themselves as attractive substrates for these low-threshold detectors. Carbon’s low nuclear mass provides a better kinematic match for low-mass dark matter candidates, and diamond’s high speed of sound and long phonon lifetime have been shown to enhance phonon collection efficiency, further improving detector sensitivity. In this talk, we present results from our characterization of these detectors.
| Main Contribution topic | Instrumentation for Dark Matter searches |
|---|---|
| Secondary contribution topic | Direct detection |