Low Background Studies at the Soudan Underground Laboratory-9/20/2002 1
Low Background Studies at the Soudan Underground Laboratory
The Soudan Underground Lab is located at a depth of 710 m, 2100 mwe at 47.8° N., 92.3° W
Two main rooms, each ~15 m wide by ~12 m high—CDMS II Lab is ~70 m long, MINOS Lab is ~95 m long
About 1/2 of existing space is available now or by mid-2003
Muon flux <1/100 m-2-s-1; rock radioactivity typical of other sites
Marvin L. Marshak University of Minnesota
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 2
Soudan Laboratory Layout
CDMS II (Soudan 2) Lab
Mine Shaft
MINOS Lab
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 3
Soudan Laboratory Assets
Existing space with utilities and management/staff infrastructure experienced in installation and operation of science experiments (Soudan 2, decay, MINOS, CDMS II)
Neutrino beam (in 2005) Critical mass of scientific
activity—MINOS and CDMS II Support facilities for scientists—
housing, etc. Experience with liability,
permitting, environmental and legal issues
The Soudan Lab is currently the largest Neutrino and Subterranean Science (NeSS) laboratory in the United States
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 4
Access to Underground Lab
Three compartment shaft with each compartment ~4 ft. x 6 ft.
Maximum length ~33 ft. Maximum weight ~9 T Skilled staff has moved
bridge cranes, front end loaders, 5,500 T MINOS Detector, CDMS II cryogenics etc. to underground lab
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 5
Active Shield Technology
Muon rate at Soudan is already low enough for some experiments: supernovae, semiconductors etc.
Soudan 2 used active shield—veto when muon passes through or near region of detected energy
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 6
Active Shield Technology
Most serious backgrounds are muon-induced neutrons and gammas
Gammas are mostly short-range
Rock radioactivity backgrounds are independent of depth
Recent data and models suggest neutrons are reasonably well-understood
Eneutron vs. Eµ (Y. F. Wang et al.)
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 7
Active Shield Technology
LVD Data on Neutron Distance and Time (M. Aglietta et al.)
Low Background Studies at the Soudan Underground Laboratory-9/20/2002 8
Future Plans
The Soudan Underground Laboratory is an active and exciting location to do science and technology
Seek potential users to collaborate in active shield design and implementation (likely experiment specific)
For further information:Earl Peterson [email protected], Priscilla Cushman [email protected] or Marvin Marshak [email protected]