Cryogenic Dark Matter Search - Proposed Upgrades: SuperCDMS and GEODM

Proposed Upgrades: SuperCDMS and GEODM

SuperCDMS is the successor to CDMS II. The "super" refers to the larger, improved detectors. There are actually three generations of Super CDMS planned:

1. SuperCDMS Soudan, with 9.3 kg of active detector mass made of 15×620 g germanium discs (76.2 mm/3″ diameter × 25.4 mm/1″ thick). This has been operating since March 2012.
2. SuperCDMS SNOLAB, with 100–200 kg of active detector mass, made of 1380 g germanium discs (100 mm/3.9″ diameter × 33.3 mm/1.3″ thick). Development is underway, and it is hoped construction will begin in 2014. The deeper SNOLAB site will reduce cosmic ray backgrounds compared to Soudan.
3. GEODM (Germanium Oobservatory for Dark Matter), with more than 1000 kg of detector mass. Preliminary planning hopes to install this in the DUSEL laboratory.

Increasing the detector mass only makes the detector more sensitive if the unwanted background detections do not increase as well, thus each generation must be cleaner and better shielded than the one before. The purpose of building in ten-fold stages like this is to develop the necessary shielding techniques before finalizing the GEODM design.