1. Cosmic Induced Backgrounds D. Reyna Argonne National Lab

2. 19 May 2006D. Reyna -- Argonne National Lab2 Correlated Backgrounds n Gd  ~ 8 MeV n deposits energy Fast Spallation Neutrons Muon induced radioactive isotopes

3. 19 May 2006D. Reyna -- Argonne National Lab3 Vertical Muon Spectrum

4. 19 May 2006D. Reyna -- Argonne National Lab4 Angular Correlation For more info: hep-ph/0604145

5. 19 May 2006D. Reyna -- Argonne National Lab5 Angular Correlation vs. Energy

6. 19 May 2006D. Reyna -- Argonne National Lab6 Expected Total Rates Muon Energy Loss ~217 MeV / mwe at low energies Hemisphere overburden

7. 19 May 2006D. Reyna -- Argonne National Lab7 Overburden Geometries 30 mwe 60 mwe Hemisphere Flat

8. 19 May 2006D. Reyna -- Argonne National Lab8 Simulated Near Lab 4m 20m 12m 4m 5m 4.5m 1.5m 20m

9. 19 May 2006D. Reyna -- Argonne National Lab9 Detector Configuration Side View Top View 5m 4m 3.9m 2.7m 2.1m 4m 3.2m 2m 1.4m Outer Muon System Oil Buffer Target γ Catcher 10cm Steele

10. 19 May 2006D. Reyna -- Argonne National Lab10 Detector Rates Muons in Outer Muon System1027 Hz Muons in Target + GC355 Hz Neutrons in Target + GC0.35 Hz Neutrons in Target + GC (with no muon in Target + GC) 0.17 Hz Neutrons in Target + GC (with no muon in outer muon system) 0.03 Hz

11. 19 May 2006D. Reyna -- Argonne National Lab11 Some Final Observations Only a preliminary look at simulation –Some evidence of increased n rates from nearest rock wall –Exact rock composition needed –Shielding can be improved Does not address backgrounds generated from muons within the detector volume