Rejecting Outer Radius Backgrounds in SuperCDMS High Voltage Dark Matter Searches

Abstract

SuperCDMS searches for Dark Matter in the form of WIMPs. SuperCDMS is able to reject most common background events by discriminating between electron and nuclear recoils. In the CDMS low ionization threshold experiment mode, electron recoil discrimination is sacrificed when applying a stronger electric potential across the detector. The electric field associated with this potential is not uniform, and the amplification of the phonon signal caused by drifting charges through this potential creates a radial dependence on the reconstructed energy. This thesis explores a new method of identifying and rejecting events at the edge of the detector in order to improve the ratio of signal to background by excluding background events with improperly reconstructed energy.