PMMA (polymethyl methacrylate)doped with a scintillating fluor
2 ft x 2 ft x ½ inch
Read out by 10 stage
EMI 9256 photomultiplier tube
The Chicago Air Shower ArrayThe Chicago Air Shower Array
recycling retired detectors from
the Chicago Air Shower Array
located in the Utah Desert:
1089 stations, 15m spacing
covering 0.23 square km
Barometric Pressure (mmHg)
727 747
4-F
old
Coi
nci
den
ces
/ 2 h
ours
3000
4200
• Statistical error bars shown• 1.3% decrease per mmHg
Marian High School’s Measurement of Cosmic Ray Rate vs. Barometric Pressure
http://marian.creighton.edu/~besser/physics/barometer.html
Mount Michael Benedictine High School
“The Science Teacher”, November 2001
Cosmic Ray Observatory Project
Collecting Data with CROP DAQ Card Interface
Doing an Efficiency Scan
1. Disconnect the 4 signal cables from the DAQ card. These are the cables that connect to your 4 detectors.2. Open the CROP_DAQ LabVIEW Program.
3. Click on the "Efficiency" tab make sure the Efficiency Scan button is ON(lit up).
4. Click on the "Threshold Scan" tab make sure the Threshold Scan button is OFF.
5. Click on the "Data Collection Settings" tab and set the timer ON (green button lit up).
6. Click on the "Data Acquisition" tab and to begin run click on (upper left corner under the Edit menu).
http://crop.unl.edu/tutorials/Online help and tutorials available.
On-Line Oscilloscope Cheat Sheets
http://unlhep2.unl.edu/~CROP/oscihomepage.html