1. SNOLAB is drawing on expertise developed by the SNO collaboration for screening materials for new experiments. Material Screening DUSEL Town Meeting 2-4 November 2007 Ian Lawson SNOLAB

2. Ge Gamma Counter  Low Background Counting available for the experiments.  HPGe detector manufactured by Princeton Gamma-Tech, the crystal is 206 cm 3 with an active mass of 1096 g.  Presently being used by SNO(+), EXO, PICASSO, DEAP/CLEAN.  Samples are usually counted for two weeks, longer for low activity samples. Material Screening DUSEL Town Meeting 2-4 November 2007Ian Lawson SNOLAB

3. Ge Gamma Counter  Sensitivity is comparable to other Ge detectors worldwide.  1 L or 180 mL sample sizes, placed in Marinelli beakers.  Calibrated with mixed radionuclide standards and sources such as 152 Eu, 60 Co, and 137 Cs.  Shielding is 5 cm OFHC copper and 20 cm lead, underground for more than 10 years. Material Screening No shielding Shielding DUSEL Town Meeting 2-4 November 2007 Ian Lawson SNOLAB

4. Material Screening ESC (Electrostatic Counter)‏  8 counters on site.  Self contained samples connected directly to the recirculating loop. Other samples placed in polypropylene cylinders with N 2 or Ar gas recirculated through chamber.  Turnaround time 1 month (3 months notice recommended)‏ 2 weeks/sample + 2 weeks for background. DUSEL Town Meeting 2-4 November 2007Ian Lawson SNOLAB

5. Radon Emanation Chambers  Used extensively for counting materials used in the SNO experiment.  sensitivity ~50 decays per day. ICP-MS  Association with facility at NRC (National Research Council) ICP-MS facility in Ottawa.  Tuned to maximize sensitivity to U and Th at sub ppt levels. K limits to < 100 ppb. Material Screening DUSEL Town Meeting 2-4 November 2007Ian Lawson SNOLAB

6. Facility Usage and Future Prospects Ge Gamma Counter  It is anticipated that this detector will be fully utilized for the next five years by the existing SNOLAB experiments as their construction proceeds.  Future possibility of adding 1 or 2 more detectors to expand counting capabilities. ESC (Electrostatic Counters)‏  Currently not utilized at 100%, and should meet current needs.  No expansion anticipated. Rn Emanation Chamber  Meets current needs, no expansion anticipated. Material Screening DUSEL Town Meeting 2-4 November 2007Ian Lawson SNOLAB