Transcript Enhancing the High School Physics Experience with Cosmic Ray Research: The Cosmic Ray Observatory Project (CROP) in Nebraska • • • • Overview and status Lessons learned in.

Enhancing the High School Physics Experience with
Cosmic Ray Research:
The Cosmic Ray Observatory Project (CROP) in Nebraska
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Overview and status
Lessons learned in 6 years
Education and training benefits
Like-minded H.S. cosmic ray efforts
in the U.S. and elsewhere
Gregory Snow
UNL Department of Physics and Astronomy
December 16, 2008
AGU meeting, San Francisco, California
The Fantastic Four ®
©1996 Marvel Comics
CROP article in Lincoln Journal Star, 7 August 2003
How a cosmic-ray air shower is formed and detected
Primary cosmic rays
(mostly protons or light nuclei)
impinge on earth’s atmosphere from outer space
“Air shower”
of secondary
particles
formed by collisions
with air molecules
Grid of particle detectors
intercept and sample
portion of secondaries
1. Number of secondaries
related to energy of primary
2. Relative arrival times
reveal incident direction
3. Depth of shower maximum
related to primary particle
type
Event timing
and direction
determination
A few facts
• Funded by $1.34 Million NSF grant, 2000-2007
• Co-PIs Greg Snow and Dan Claes
• 26 Nebraska and 5 Colorado schools enlisted and trained
in summer workshops of duration 2-4 weeks, about
5 new schools per summer
• Hosted 2 one-day meetings each academic year for
participants from all years to report results, exchange
faulty equipment, receive equipment and software
upgrades, refresh training or train new students
• External evaluation of this period has shown that CROP
has accomplished most of its educational and scientific
goals listed in the original proposal
• CROP has also served as a great training ground for
staff (undergrad, grad students) at UNL
Highlighted squares = participating schools
The Chicago Air Shower Array
• CROP uses retired detectors from the Chicago Air Shower Array
• 1089 boxes each with:
• 4 scintillators and photomultiplier tubes (PMT)
• 1 high voltage and 1 low voltage power supply
• Two removal trips (September 1999, May 2001) yielded over
2000 scintillator panels, 2000 PMTs, 500 low and power supplies
The CROP team at Chicago Air
Shower Array (CASA) site
U.S. Army Photo
September 30,
1999
Equipment recovery trip to Dugway, Utah, May 2001
CROP data acquisition electronics card
Developed by Univ. Nebraska, Univ. Washington, Fermilab (Quarknet)
Programmable
logic device
Time-to-digital
converters
To PC
serial port
GPS receiver
input
Four analog
PMT inputs
5 Volt
DC power
• 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
Event
counter
Discriminator
threshold
adjust
User-friendly, LabView-based control and monitoring GUI
Event
counter
Two detectors
firing at the
same time
Data stream
for each
event
Elapsed
run
time
Summer 2000 workshop
17 July 2000
Summer 2001 Workshop
Summer 2002 workshop
Summer 2004 Workshop Activities
Detector assembly and testing
Summer 2004 Workshop Activities
Oscilloscope and DAQ card lessons
Summer 2004 Workshop Activities
Practice experiments to be performed at school
Summer 2004 Workshop Activities
Detectors return to school
Detector set-ups at schools
“Telescope” set-ups for
indoor experiments
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Rate vs. barometric pressure
Day-night variation
Rate vs. angle from zenith
Light attenuation vs. distance
from PMT
April 2001 participant meeting at UNL
Marian High School
students presenting
results and discussing
cosmic rays with
Prof. Jim Cronin,
University of Chicago
Marian High School’s Measurement
of Cosmic Ray Rate vs. Barometric Pressure
4200
• Statistical error bars shown
4-Fold Coincidences / 2 hours
• 1.3% decrease per mmHg
3000
727
Barometric Pressure (mmHg)
747
Installation at Lincoln High School, August 2003
GPS receiver
Several school in process of moving to the roof after indoor experiements
Other Rooftop Installations
Some schools have installed
detectors on their rooftops
and are studying coincidence
rates vs. separation
Summer 2005 1-week refresher workshop
• Over half the participating schools attended
• New student (and teacher) training
• Preparation for rooftop data taking
Omaha’s Creighton University Joined Us
Fr. Tom McShane
with his
“Berkeley”
CR detector
Masters degree student
Lyle Sass,
our “ambassador” to
NE high schools
Morning classroom sessions
Presented abbreviated version
of our full classroom curriculum
Dan explaining detection of
radiation with electroscopes
Afternoon lab sessions
New students had exposure
to full detector assembly
and testing procedures
Each school’s detector set ups exercised
Setting discriminator thresholds
and efficiency scans for high voltage
settings
Moving detectors outside for overnight
air shower data taking run
Each school made new rooftop enclosures
Excellent extensive air shower
data taking run overnight
New enclosures making it to rooftops
Westside High School
Omaha, NE
Weights, important !!
Some lessons learned in 6 years
• Big variation among schools in independent activity/investigations
during school year. Some real successes, some inactive sites
• Close contact very important during academic year
• Scheme for replacing/training new students as classes graduate
important
• Classroom integration, affect on curriculum is not automatic.
Scheme to guide this needed.
• Hardware and software delays create frustration and idleness
• Hard to recruit for long summer workshops
• High school schedules are packed, hard to get full participation
in academic year Saturday meetings of all participants
Mount Michael High School
“The Science Teacher”, November 2001
CROP research has been the basis for several
student science fair projects
that have placed highly in national competitions
Ben Plowman
Lincoln High School
Study of light attenuation in CROP scintillators as a function of
distance from the photomultiplier position
Nebraska’s 2006 PAEMST Science Teacher Award Recipient
Jim Rynerson
Physics Teacher
Lincoln High School
CROP participant since 2001
Successes of CROP staff at UNL
CROP undergraduates
Andy Kubik: Northwestern University
Andrea Fuscher: Vanderbilt University
CROP undergraduate
Katie Everett
now in physics grad school
University of Buffalo
Successes of CROP staff at UNL
Teachers College Masters Degree
Student Tracy Evans
has gone on to high school science
teaching in Nebraska
CROP undergrad Jason Keller
now in physics grad school
At UNL
Our first advanced degree
Xioashu Xu
M.S. degree in Statistics
August 2006
“Probability of Extensive Air Showers Based on the
Study of Accidental Coincidences in the Cosmic Ray
Observatory Project”
Submitted NSF GK12 proposal Fall 2008
• Main thrust: statewide growth to ~100 schools + continuous
data-taking and analysis
• State schools administered through 19 Educational Service Units
• Present schools serve as “hubs” for expansion in each ESU
• Train through regional workshops, 2-3 per summer
NALTA
The North American Large-Scale Time-Coincidence Array
WALTA
ALTA
SALTA
CROP
SCROD
PARTICLE
TECOP
http://csr.phys.ualberta.ca/nalta/
• Includes links to individual project
Web pages
CHICOS
Pierre Auger northern
hemisphere site in
southeast Colorado
Los Angeles Area Schools
(Animation by L.A. school teacher)
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Institutions
LA area schools
California Institute of Technology
California State University, Northridge
University of California, Irvine
Funding
• Caltech
• NSF Nuclear Physics
• 164 detector stations recovered
• 2 detectors per school foreseen
European High School Cosmic Ray Sites
• Reporting at the
Lisbon meeting,
September 2006
• Portugal
• The Netherlands
• Belgium
• Greece
• Italy
• Denmark
• Poland
• Russia
• Sweden
One slide summary of the situation in Europe
• There are a few mature and several emerging like-minded efforts
• Teams of high school teachers and students work with university
physics groups to study extensive air showers using school-based
detectors
• Projects embrace both educational and scientific goals
• All projects employ plastic scintillators placed on high school
rooftops, except EEE in Italy which will employ Multi-Gap
Resistive Plate Chambers
• GPS receivers give local time stamp for cosmic ray events recorded
locally, internet allows teams to share data and search for
building-sized or city-sized showers and long-distance correlations
• Most efforts are/have developed readout electronics, data
acquisition software and analysis techniques independently, relying
on local expertise
• Full fledged start-up or expansion limited by funding and manpower
• Desire for a more global, unified approach to eliminate duplication
of effort and to standardize/share detectors, procedures,
data format, curriculum materials, …
Sites in The Netherlands
www.hisparc.nl
At present: 5 clusters in NL, with national project manager
Groningen, Utrecht, Nijmegen, Leiden, Amsterdam
(each with their own leader)
Sites in The Netherlands
At present: About 42 detector stations operational or pending
Sites in The Netherlands
Car top ski racks!
Present price per school:
6500 Euros
(20% cost is scintillator)
GPS
antennas
Sites in Portugal
PORTUGAL
5m
9
Belgium
The HELYCON Detector Module
Greece
Aiming toward a worldwide network
of cosmic ray detectors