A Statewide Outreach and Education Experiment in Nebraska The Cosmic Ray Observatory Project Dan Claes University of Nebraska APS-DPF JPS2006 Monday, October 30, 2006

The Fantastic Four ® ©Marvel Comics

CROP article in Lincoln Journal Star, 7 August 2003

The Chicago Air Shower Array Located in the Utah Desert 1089 stations, 15m spacing covering 0.23 square km each houses 4 scintillators w/tubes 1 high and 1 low voltage supply CROP recycles retired detectors from the Chicago Air Shower Array

September 30, 1999 The CROP team at the Chicago Air Shower Array (CASA) site U.S. Army Photo 2000 scintillator panels, 2000 PMTs, 500 low and HV power supplies now at UNL CASA detectors’ new home at the University of Nebraska

250 miles 450 miles The Cosmic Ray Observatory Project A grid of cosmic ray research stations expanding across the state

$1.34 Million NSF grant, co-funded by ESIE and EPP divisions Co-PIs Greg Snow and Dan Claes 26 Nebraska and 5 Colorado schools enlisted trained in (2-4 week long) summer workshops about 5 new schools each year Colorado program (SALTA) was a joint effort by CROP, WALTA, ALTA External evaluation: CROP has accomplished most of the educational & scientific goals listed in the original proposal CROP also serves as excellent training for student (undergrad, graduate) staff at UNL NSF

CROP Workshops

Oscilloscope training

Tearing the old CASA counters apart

Scraping, sanding and polishing

Wrapping & light-tighting

Electronics lessons

Four analog PMT inputs Programmable logic device Time-to-digital converters 5 Volt DC power To PC serial port Discriminator (adjustable threshold) GPS receiver input Event counter CROP data acquisition electronics card Developed by Univ. Nebraska, Fermilab (Quarknet), Univ. Washington 43 Mhz (24 nsec) clock interpolates between 1 pps GPS ticks for trigger time TDC’s give relative times of 4 inputs with 75 picosecond resolution

User-friendly, LabView-based control and monitoring GUI Two detectors firing at the same time Data stream for each event Event counter Elapsed run time

April 2001 participant meeting at UNL Marian High School students presenting results and discussing cosmic rays with Prof. Jim Cronin, University of Chicago

Barometric Pressure (mmHg) Fold Coincidences / 2 hours Statistical error bars shown 1.3% decrease per mmHg Marian High School’s Measurement of Cosmic Ray Rate vs. Barometric Pressure

Mount Michael Benedictine High School “The Science Teacher”, November 2001

Ben Plowman, Lincoln High School state finalist in the American Junior Academy of Sciences invited 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.

UNL Physics Department roof February 2002 Marian High School March 8, 2002 Westside High Omaha note the theater weights! Several schools are running detectors on their roof.

Simultaneous data-taking at 3 sites UNL Ferguson Hall Lincoln High Zoo School DAQ card discriminator thresholds set to obtain ~ 100Hz singles rates At each school, require 3-fold coincidence of detectors Events “close” in time (within 1 millisecond) have been observed, but NO events close enough (few microseconds) to signal a single air shower 1 mile

Summer 2005

Andy Warta University of Minnesota Peter Jacobson Tulane University Andy Kubik Northwestern University Andrea Fuscher Vanderbilt University Katie Everett University at Buffalo Jason Keller University of Nebraska Tracie Evans Ralston Public Schools Xiaoshu Xu Master’s Degree in Statistics University of Nebraska

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). Online help and tutorials available.

On-Line Oscilloscope Cheat Sheets

Big variation among our schools in independent activities. Some real successes, some inactive sites Hardware/software delays create frustration and idleness Close contact very important during academic year A scheme for replacing/training new students as classes graduate is very important High school schedules are packed (full participation in academic year Saturday meetings is difficult) Classroom integration, affect on curriculum not automatic. Need to be tied directly to standards! Hard to recruit for long summer workshops Some Lessons Learned Our expansion phase (to ~100 schools) will be developed through shorter remote workshops hosted by the regional offices of the state’s 19 Educational Service Units.

Selected 120 mile radius (2 hr trips) arcs shown

If time allows…

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 ,152 feet above sea level SALTA: Snowmass Area Large Time-Coincidence Array Empire Clear Creek High School, Empire, CO

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

Henderson Mine Visit Dec 4, 2003 hosted by Chip deWolfe Marc Whitley Aspen High School Diana Kruis Basalt High School Hans-Gerd Berns University of Washington Dan Claes University of Nebraska Michelle Ernzen Lake County School Laura French Roaring Fork Valley Nancy Spletzer Clear Creek High School Scouted 3 possible locations between depths of 2800  3900 ft 110 power available

A portable stand held each muon telescope. Detectors telescoped pair with coincidence requirement against noise sandwiching a ¼ inch lead sheet were configured into muon telescopes 2 modules taken down into the mine Detectors moved at 2-3 week intervals since dust posed a problem for a PC we housed a low-power serial digital data logger alongside the DAQcard Desktop Base Station An ~identical pair of modules ran in a fixed location (surface office) to establish our baseline

SALTA’s Henderson Project was launched September 29, 2004

Basalt students move the detectors to the next location Clear Creek students set up the satellite modules

Rates at Henderson surface base station (10,337 ft above sea level) = 2.5  rates at Lincoln, NE (elevation: 1189 ft) Data collected between Sept 29 – Dec 8, 2004 monitored 4 locations between depths of ft Raw rates in muon telescopes seen to drop from 10 Hz (surface rate) → 1.5 Hz → 0.5 Hz → 0.3 Hz Some preliminary observations

Channel 0,1 coincidences Channel 2,3 coincidences Successive teams of high school students have been analyzing the data identifying stable data run periods bad data channels …learning about the statistical nature of random events …and calculate accidental coincidence rates and statistical error