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