programmable logic device
DESCRIPTION
4200. 4-Fold Coincidences / 2 hours. Event counter. 3000. 727. 747. Barometric Pressure (mmHg). 10 stage EMI 9256 photomultiplier tube. equipment recycled & refurbished from the Chicago Air Shower Array. 60 cm 60 cm x 1.25 cm. - PowerPoint PPT PresentationTRANSCRIPT
Programmablelogic device
Time-to-digitalconverters
5 VoltDC
power
To PCserial port
Four analogPMT inputs
Discriminatorthreshold
adjust
GPS input
Eventcounter
Developed by Univ. Nebraska, Fermilab (QuarkNet), Univ. Washington
• 43 Mhz (24 nsec) clock interpolates between GPS 1 pps for trigger time• TDC’s give relative times of 4 inputs with 75 psec resolution
2 detectorsfiring at thesame time
Data stream
for eachevent
Eventcounter
Elapsedrun
time
PMMA (polymethyl methacrylate)doped with a scintillating fluor
10 stage EMI 9256 photomultiplier tube
0
0.2
0.4
0.6
0.8
1
1.2
950 1000 1050 1100 1150 1200 1250 1300 1350 1400 1450 1500
Barometric Pressure (mmHg)727 747
4-F
old
Coi
nci
den
ces
/ 2 h
ours
3000
4200
• Statistical errors 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 connected 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 "Threshold Scan" tab; make sure the Threshold Scan button is OFF.
5. Click "Data Collection Settings" tab and set the timer ON (green button lit).
6. Click the "Data Acquisition" tab and to begin run click on (upper left corner of menu bar).
http://crop.unl.edu/tutorials/Online help and tutorials available:
On-Line Oscilloscope Cheat Sheets
http://unlhep2.unl.edu/~CROP/oscihomepage.html
A Statewide Outreach and Education Experiment in Nebraska
The Cosmic Ray Observatory ProjectDaniel Claes & Gregory Snow
Supported by theNational Science Foundation
60 cm 60 cm x 1.25 cm
Teaches and studentstrained in intensive
workshop experiences
Examples of independent student projects
Online resources
Photomultiplier tubes are working!
http://crop.unl.edu
Ben Plowman, Lincoln High Schoolstate finalist in the American Junior
Academy of Sciencesinvited to present at
the Washington, DC, meeting (February 2005)
Rudy Resch and Kent Shirer presented a poster on
their follow-up work at the Intel International Science
and Engineering Fair (Phoenix, May 2005) and placed fourth in
the physics category.
• Two removal trips (September 1999, May 2001) yielded over 2000 scintillator panels, 2000 PMTs, 500 power supplies• Sufficient hardware for all Nebraska high schools
100 mile circles centered on selected Education Service Unit (ESU) office
locations show how at least 1 of 3 planned annual training workshops
can be within a day’s trip of every school in the state.
Workshop locations will be rotated among the 19 ESUs during our expansion phase.
Typical school setup and
schools enlisted During the first
5 years of the project.
CROP has now trained 36 science instructors and over 150 students, representing 29 school teams, in the hands-on maintenance and use of their own student-built cosmic ray particle detectors.
Data acquisition cardand LabView interface
Expansion Plans
engaging teams of high school teachers and students in a genuine long-term cross-disciplinary research experience: studying correlations of extended cosmic ray air showers across the state of Nebraska
Summer 2005 Workshopincluded an overnight
shower array on the lawn
equipment recycled & refurbished
from theChicago Air
Shower Array