1. Nebraska’s Statewide Outreach and Education Experiment The Cosmic Ray Observatory Project Dan Claes University of Nebraska-Lincoln Thursday, December 11, 2003 Washington Area Large Time-coincidence Array Henderson Mine: Cosmic Ray Flux Measurements A High School Outreach Opportunity

2. CROP article in Lincoln Journal Star, 7 August 2003

3. CROP Workshops

4. PMMA (polymethyl methacrylate) doped with a scintillating fluor Read out by 10 stage EMI 9256 photomultiplier tube Recycling material inherited from The Chicago Air Shower Array 2 ft x 2 ft x ½ inch

5. EMI Photomultiplier tubes are working Typical efficiency of counters 85% - 95%

6. The Washington-Area Large-Scale Time-Coincidence Array http://www.phys.washington.edu/~walta Seattle area map showing schools CROP’s closest relative University of Washington, Seattle Jeff Wilkes, et al. also using refurbished CASA detectors WALTA / CROP / FNAL collaboration developing DAQ PC electronics card Funding limited, but used QuarkNet association to fund 1 st WALTA workshop, August 2001

7. WALTA/QuarkNet One-week Summer Workshop University of Washington August 2001 Seattle teachers and WALTA staffRefurbishing CASA scintillators

8. Colorado Aspen High School, Aspen, CO Basalt High School, Basalt, CO Roaring Fork Valley High School, Carbondale, CO Lake County High School, Leadville, CO The highest-elevation school in U.S. -- 10,152 feet above sea level SALTA: Snowmass Area Large Time-Coincidence Array

9. Polishing scintillator edges outside Conference Center Making detectors light-tight SALTA Workshop, July 2001, Snowmass, CO mass phototube gluing

10. Leadville

11. Henderson Mine Visit Dec 4, 2003 hosted by Chip deWolfe Marc Whitley Diana Kruis Nancy Spletzer Aspen High School Basalt High School Clear Creek High School Michelle Ernzen Laura French Lake County School Roaring Fork Valley Hans-Gerd Berns University of Washington Dan Claes University of Nebraska

12. Issues: Can't survey the proposed site, but can find spots away from glory hole ( where blasting still common & overhead rock broken up ) Topological graphs and CAD tools can provide good estimates of overburden at survey-able spots. where dust may be a problem for a PC can house a low-power serial digital data logger Hans Berns experimenting with Acumen Instruments Databridge development kit

13. Scouted 3 possible locations between 2800-3900 ft depths 110 power available

14. Detectors telescoped pair with coincidence requirement against noise sandwiched with lead sheet Configuration being explored Paul Edmon, Jeff Wilkes (UWash), Dan Claes (UNL) A second ~identical detector will run in a fixed location (surface office) to establish a baseline At mining level (3000 mwe) any one (2 ft  2 ft) panel can be expected to count only a handful of events / day will want to gang several together to increase total area May need week(s) long runs All the SALTA schools are eager to participate! Henderson may be comfortable with 2-week intervals

15. Timeline: September 27 - SALTA teams invited to UNL’s Fall Saturday workshop for re-training with new DAQ cards (travel expenses and stipends covered by SALTA/CROP funds) December 4 - retrieved NIM crates (on loan from FNAL-PREP) - Henderson Mine meeting with Chip deWolfe - Claes, Berns, all SALTA teachers January - finalize locations to survey - characterize all SALTA detectors: efficiency, threshold settings - finalize detector configurations February – orientation at Henderson Mine for all SALTA participants March-April – data collection Note:Students (over 14) will be allowed. Safety escorts required for every access. Need to work around SALTA teachers’, Henderson schedules.

16. - S. Miyake et al, Nuovo Cim., 32, 1505 (1964) COR - P.H.Barret et al, Rev. Mod. Phys., 24, 133 (1952)  - L.M.Bollinger, PhD Thesis, Cornell University (1952) - J.Clay and A. von Gemert, Physica, 6, 497 (1939) - J.C.Barton et al, Phil. Mag., 6, 1271 (1961) OR – C.A.Randal and W.E.Hazen, Phys. Rev., 81, 144 (1951) – B.V.Sreekantan and S.Naranan, Proc. Ind. Acad. Sci., 36, 97 (1952) M - Y. Miyazaki, Phys. Rev., 76, 1733 (1949)  - V.C.Wilson, Phys. Rev., 53, 337 (1938) 8400 meters water equivalent Kolar Gold Field zero counts in 2 months (Miyake 1964)