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Development of Giant Air Shower in Earth’s Atmosphere

Development of Giant Air Shower in Earth’s Atmosphere

Primary cosmic ray

Mostly muons, electronsand photons at Earth’s

surface

A map of the northern Pierre Auger detector site in Millard County, Utah.

A map of the southern Pierre Auger detector site in Mondoza province, Argentina.

Pierre Auger, discoverer of cosmic ray air showers.

Victor Hess after his 1912 balloon flight, during which he discovered

cosmic rays from space.

Two possible sources of cosmic rays

Colliding galaxies

Active galacticnucleus

Possible Source of Concident,Widely-Separated Showers: the GZ Effect

(Gerasimova-Zatsepin)

Cosmic ray iron nucleus

Optical photon from the sun

Earth’s Surface

Nuclear fragments from photo-disintegration

• Watson and Medina-Tanco revisit this 1960-predicted phenomenon in astro-ph/9808033

• Calculation for 6 × 1017 eV Fe Mn + proton

• Shower separations of 100’s to 1000’s of kilometers possible, dominated by deflections in interplanetary magnetic fields

• Rates not encouraging

The Pierre Auger Observatory uses 1600 particledetectors spaced uniformly over 3000 square kilometers

to record cosmic ray air showers. On dark nights, sensitive light sensors observe the faint fluorescence caused by

collisions of air shower particles with air molecules in the atmosphere.

“Air shower” of secondaryparticles formed by collisionswith air molecules

How a cosmic-ray air shower is formed anddetected

Primary cosmic ray (mostly protons) impinges onearth’s atmosphere from outer space

Grid of particledetectorsintercept andsample portionof arrivingsecondaries

• Number of secondaries related to primary cosmic ray energy

• Relative arrival time of secondaries tells incident direction

“Air shower” of secondaryparticles formed by collisionswith air molecules

How a cosmic-ray air shower is formed anddetected

Primary cosmic ray (mostly protons or light nuclei) impinges on earth’s atmosphere from outer space

Grid of particledetectorsintercept andsample portionof arrivingsecondaries

• Number of secondaries related to primary cosmic ray energy

• Relative arrival time of secondaries tells incident direction

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The Cosmic Ray Energy Spectrum

Counties and Congressional Districtsin Nebraska

24”

24”Plastic scintillator

Photomultiplier tube

Schematic of typical CROP high-school set up (not to scale)

Inventory of equipment at school• 4 weather-proof enclosures for detectors• 4 cosmic-ray detectors (polystyrene scintillator tiles and photomultiplier tubes)• GPS receiver• Power supply for detectors (not shown)• Personal computer for data acquisition, monitoring, and data analysis with connection to Internet• Triggering and data-acquisition electronics card connected to PC• Software for PC• Cables from rooftop detectors and GPS to PC

GPS receiver

Cables bring signals to PC

Weather-proof detector enclosures

PC inside classroom

Cosmic ray detector inside each enclosure

CASA counter

The CROP Advisory Panel

Professor Ronald Bonnstetter, Director of Secondary Science Education, University of Nebraska, Lincoln NE.

Dr. Susana Deustua, research astronomer at the Lawrence Berkeley Laboratory, and project scientist for the Hands-on Universe Project.

Dr. Ernest Malamud, senior scientist at Fermilab, founding director of SciTech hands-on science center, Aurora IL

Ms. Olivia Diaz, 1997-99 Executive Director of SciTech, Aurora IL.

Dr. Paul Mantsch, senior scientist at Fermilab, Project Director of Pierre Auger Observatory.

Ms. Mary Lou Pagano, high school math teacher, K -12 math dept. chair, Kansas City MO.

Mr. John Rogers, physics teacher Westside High School, Omaha NE.

Professor John Swain, physics professor, Northeastern University, Boston MA, and collaborator in the Pierre Auger Giant Air Shower Project.

Chicago Air Shower Array, Dugway, Utah

• 1089 boxes with 4 scintillators and tubes in each box 1 high voltage and 1 low voltage supply in each box

• G. Snow visited site on August 10, 1999, for logistics of removing approx. 25 boxes for first year of CROP

• Snow, Claes, 2 students filled Ryder truck Sept. 30 - Oct 2 and drove to Lincoln

• Univ. of Nebraska Vice Chancellor for Academic Affairs paid for removal trip ($4000)

• Funding for removal expenses for subsequent CROP years requested in NSF Teacher Enhancement proposal

• Many thanks to the CASA collaboration!!!!

The Cosmic Ray Observatory Project (CROP)University of Nebraska

Lincoln, NebraskaUSA

Gregory Snow and Daniel ClaesPrincipal Investigators

• Start-up support since 1994 has been obtained from:• The University of Nebraska• The NSF-funded Math and Science Initiative• Chicago Air Shower Array (spare scintillators and PMTs)• Fermilab (long-term loan of trigger electronics and power

supplies for prototype work)

• Major funding proposal submitted in August 1999 to the NSF Teacher Enhancement Program

• $1 Million over 5 years• High school teacher and student team workshops• Learn physics of cosmic rays, extended air showers, particle

detectors, data acquisition, data analysis, GPS time stamp, installation at school, sharing local data over Internet with other sites, career opportunities in science, emphasis on women, minority and rural participation

A Model for Pierre Auger Education and Outreach

The Cosmic Ray Observatory Project (CROP)

THE IDEA• Statewide outreach project which involves:

• Nebraska high school students• High school teachers• College undergraduates

in studies of extended cosmic ray showers.

• Each participating high school has a stand-alone experiment.• Retired CASA detectors in weather-proof enclosures on roof• GPS receiver gives local time stamp for shower arrival• PC inside school takes data at each site• Student teams share data over Internet searching for

time coincidences

THE SCIENCE OF CROP• Each school records building-sized showers -- plenty of rate.

• Neighboring schools in same city (Lincoln, Omaha) see coincidences from highest-energy showers -- low rate.

• Nebraska is 450 x 250 square miles -- schools separated by very large distances explore whether showers come in large, correlated bursts. That is, does the whole state of Nebraska ever light up?

Eventually, integrate CROP data with Pierre Auger data!!(and data from other emerging school-based arrays)

CROPCosmic Ray Observatory Project

• A high-school based mini-Pierre Auger Project• Coarser array covering much larger area

450 miles

250 miles

The KASCADE experimentin Karlsruhe, Germany

The Cosmic Ray Observatory Project (CROP)University of Nebraska

Lincoln, NebraskaUSA

Gregory Snow and Daniel ClaesPrincipal Investigators

• $1,342,000 grant from the National Science Foundation• Teacher Enhancement program of the NSF• NSF grant period: June, 2000 - May 2004• Additional funding needed for

• Short-term R&D to optimize the stand-alone experiment at each high school

• Hardware equipment needs for each high school to supplement detectors inherited from Chicago Air Shower Array experiment

• Longer-term funding to institutionalize the project after NSF funding runs out

The CROP team at Chicago Air Shower Array (CASA)site, September 30, 1999

U.S. Army Photo

The CROP team at Chicago Air Shower Array (CASA)site, September 30, 1999

U.S. Army Photo

The CROP team at Chicago Air Shower Array (CASA)site, September 30, 1999

U.S. Army Photo

The CROP team at Chicago Air Shower Array (CASA)site, September 30, 1999

U.S. Army Photo

Storage and staging area in Hamilton Hall basement

Complete CASA boxes (four detectors inside) plus spare detectors

Stacks of scintillator pieces without photomultiplier tubes

CROP

1999-2000 CROP Activities / Milestones

• Summer 1999, team of three undergraduates:

• Worked on CROP detector prototypes• Scintillators and photomultplier tubes• Data-acquisition card interfaced to PC• GPS receiver and read-out• Gathered materials for associated teaching modules

• Two students continue during academic year

• NSF Teacher Enhancement proposal submitted August 99

• January 2000: notification of approval and funding• $1,342,000 over 5 years

• Arrangement cemented with Chicago Air Shower Array

• Retired equipment offered free of charge

• First batch of CASA equipment removed Sept. 30 - Oct. 2

• Several presentations made for recruitment of school teams

• First pilot schools identified• Lincoln Northeast High School• Lincoln High School

1999 CROP Information and Recruitment Presentations

• Nebraska AAPT, Jan. 30, Millard West High School, Omaha

• Claes

• AP Physics readers, June 17, Nebraska Union, UNL• Snow

• Nebraska AAPT, Oct. 23, Physics Dept., UNL• Claes

• Lincoln Public Schools In-service Day, Oct. 25, Physics Dept., UNL

• Claes, Snow

• Nebraska Association of Physics Teachers, Oct. 30, Fremont, NE

• Claes

• 15 complete CASA boxes from the field, each with • 4 wrapped/sealed counters• 4 mounted EMI photomultiplier tubes• 1 low voltage, 1 high voltage supply

in addition

• 19 spare counters with EMI tubes attached• 95 covered panels of scintillator (no tubes)• 52 spare (good?) photomultiplier tubes

• 27 spare low voltage supplies• 40 spare high voltage supplies

• 4 boxes of black scintillation covers• 5 unused empty station boxes• 45 white vinyl weather-proof station covers

Sufficient raw material on hand toequip >20 schools

Inventory of Equipment from 1999 RecoveryTrip to Chicago Air Shower Array

Dugway Proving Grounds, Utah

James Cronin (Univ. Chicago) and Alan Watson

(Univ. Leeds) Project Spokespersons

Argentina

Utah

Detector Sites

The Pierre Auger Observatory uses 1600 particledetectors spaced uniformly over 3000 square kilometers

to record cosmic ray air showers. On dark nights, sensitive light sensors observe the faint fluorescence caused by

collisions of air shower particles with air molecules in the atmosphere.

The KASCADE experimentin Karlsruhe, Germany

Fluorescence Detectors

Fly’s Eye IIDugway, Utah

High-ResExperimentDugway, Utah

• The Alberta Large Area Time coincidence Array (ALTA) is a collaborative project, involving the University of Alberta and provincial high schools, to search for very large area (~30,000 km2) correlations between the arrival times of cosmic ray showers observed at individual detector sites.

Other Cosmic Ray Outreach Projects

• WAshington Large Area Time coincidence Array (WALTA) is a project to investigate the highest energy cosmic rays with the participation of middle an high school students and teachers throughout the Seattle area.

• ASPIRE: Astrophysics Science Project Integrating Research and Education http://sunshine.chcp.utah.edu

The North American Large-scale Time-coincidence Array

Members of the Consortium• ALTA (University of Alberta, Edmonton, Alberta, Canada) • CHICOS (CalTech, UC/Irvine, and Cal State/Northridge, California, USA) • CROP (University of Nebraska, Lincoln, NE, USA) • WALTA (University of Washington, Seattle, WA, USA)

ALTA Detector (School) Site MapSurrounding

Edmonton, Alberta, Canada

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Shmoos arrive at CalTech

Refrigerator cold CO2 bubble (887 mph)

0.02 eV

Room temperature nitrogen N2 (1160 mph)

0.03 eV

Atoms in sun’s MILLION DEGREE surface0.50 eV

Energy given to each single electron whenaccelerated by AA battery 1.5 eV

Electrons accelerated by your televisionpicture tube (traveling ~1/3 speed of light)

30,000 eV

Fermi National Lab’s high energy protons 1,000,000,000,000 eV

Superball bounced over your house 4 x 1017 eV

Pitched baseball 4 x 1020 eV

Slammed hockey puck 1 x 1021 eV

Recall: 1 joule = 6.2 x 1018 eV

The highest energy Cosmic Rays areSUBATOMIC particles carrying theenergy of MACROSCOPIC objects!

4 x 1021 eV = 60 joules

The Cosmic Ray Energy Spectrum

FERMILAB’s protonsFERMILAB’s protons

Bounced Superball

Bounced Superball

Pitched baseballPitched baseball

Hockey PuckHockey Puck

The Akeno Giant Air Shower Array (AGASA) in Japan

• World’s second-highest energy cosmic ray event• Recorded December 3, 1993• Particles covered 4 km 4 km area• 23 detector sites recorded coincident hits• Plot indicates particle density at each location• Radius of yellow circle = logarithm of number of particles recorded

Primaryenergy2 1020 eV

The Akeno Giant Air Shower Array (AGASA) in Japan

• 111 detector sites using scintillation counters • Approx. 1 km spacing between sites

• Coverage about 100 square km

High Energy Cosmic RaysThe Pierre Auger Project

andThe Cosmic Ray Observatory Project (CROP)

Gregory SnowDepartment of Physics and Astronomy

University of NebraskaLincoln, Nebraska, USA

Lincoln International SchoolBuenos Aires, Argentina

April 10, 2000

Outline

• Cosmic rays and extended air showers

• The Pierre Auger Project and similar experiments

• CROP in Nebraska

• Other cosmic ray education/outreach projects

• Conclusions

http://www.auger.orghttp://www.physics.unl.edu/research/crop/crop.html

High Energy Cosmic Raysand

The Cosmic Ray Observatory Project (CROP)Gregory Snow

Department of Physics and AstronomyUniversity of Nebraska

Lincoln, Nebraska, USA

Northeastern UniversityBoston, MA

April 26, 2000

Outline

• Cosmic rays and extended air showers

• The Pierre Auger Project and similar experiments

• CROP in Nebraska

• Other cosmic ray education/outreach projects

• Conclusions

http://www.physics.unl.edu/research/crop/crop.html

The Cosmic Ray Observatory Project (CROP)

Conclusions

• CROP is underway in Nebraska

• Major funding has been secured from the National Science Foundation ($1,342,000 over 5 years)

• We look forward to:• Doing exciting cosmic-ray research with CROP detectors• Providing hands-on research experiences and involvement to high-school teachers and students throughout Nebraska and elsewhere

• Extensive use of the Internet / distance learning

• Stay tuned for news on our progress

Conclusions

• High schools across the country are becoming involved in frontier cosmic ray research

• CROP is underway in Nebraska• Major funding has been secured from the

National Science Foundation ($1,342,000 over 5 years)

• Parallel efforts are emerging in several locations in the U.S., Canada, and abroad

• The NALTA consortium has been formed for the sharing of expertise developed locally and the networking of detector arrays separated by long distances

• Stay tuned for news on our progress

The Pierre Auger ProjectThe Cosmic Ray Observatory Project (CROP)

Conclusions

• The Pierre Auger project is underway in Argentina

• CROP is underway in Nebraska

• We look forward to:• Doing exciting cosmic-ray research with the Pierre Auger and CROP detectors• Providing hands-on research experiences and involvement to high-school teachers and students throughout Nebraska and elsewhere

• Stay tuned for more news on our progress

Cosmic Ray Mysteries

• The origin and acceleration mechanism for the highest-energy cosmic rays are unknown!!

For Eprimary > 1019 eV

• Primary particles must originate from closer than about 50 Megaparsecs (Mpc)

Otherwise lose energy interacting with ubiquitous 3o Kelvin cosmic background radiation (photons)

• But there is no observed “source” within 50 Mpc of earth

• Reference distances: Diameter of Milky Way disk = 0.024 Mpc Distance to Andromeda galaxy = 0.6 Mpc

CROP

Pierre Auger northern hemisphere site in Utah

CROP-EastALTA

CHICOS

WALTA

NALTAA growing, continent-wide consortium

State of Nebraska

Pierre Auger northern hemisphere site in Utah

CROP 2000July 17 - July 21July 24 - July 28

July 31 - August 4August 7 - August 11

Lincoln Northeast High SchoolPhysics Teacher: Kent ReinhardStudents: Uyen Chu, Chris Esquibel, Michael Gallagher

Science Focus Program, Zoo School, LincolnPhysics Teacher: De TonackStudents: Peter Jacobsen, Chris Schlitz, Ryan Tiedeman

Marian High School, OmahaPhysics Teachers: Bruce Esser, Sharon GenowaysStudents: Tracy Fendrick, Amanda Carney, Elizabeth Greer

Mount Michael Benedictine High School, ElkhornPhysics Teacher: Michael LieblStudents: Jamie Antonelli, Sean Mahoney, Derek Streich

Norfolk High School, NorfolkPhysics Teacher: Dennis MillerStudents: TBA

Participating Schools, Teachers, and Students

The Muon Detector responds to significant cosmic ray events resulting from solar processes. These are mainly "Forbush" events in which there is a sharp reduction in cosmic ray intensity followed by a gradual return to earlier levels over a period of a few days. Suchevents can either be spotted by eye from the muon data or by the use of lists of such events found through the links. Students can search for such effects.

Forbush events are more easily recognised if the significant effect of variations in atmospheric pressure is first removed. The figure shows the correlation between count rate and pressure for days 14 Dec to 19 Dec. There is a clear inverse relationship between pressure and the resulting count rate. We use an approximation to this of -0.2% count rate change per millibar for correcting our muon display

University of Adelaide Cosmic Ray Experiments for Students

http://www.physics.adelaide.edu.au/astrophysics/index.html

First Semester Studies at CROP Schools

1

11

3

2

2 2

3 3

With counters spread out in horizontal plane• 3/4 and 4/4 coincidence rate vs. counter separation• Optimization of counter geometry on school rooftops

With 4 counters stacked in vertical telescope• Coincidence rate vs. barometric pressure

The Cosmic Ray Observatory Project (CROP)and

Participatory Science Using the InternetGregory Snow

Department of Physics and AstronomyUniversity of Nebraska

Lincoln, Nebraska, USA

International Conference of the Learning SciencesAnn Arbor, Michigan

June 14 - 17, 2000

Outline

• Cosmic rays and extended air showers

• CROP in Nebraska

• Specific uses of the Internet in CROP research

• Other cosmic ray education/outreach projects

• Conclusions

http://www.physics.unl.edu/research/crop/crop.html

High Schools Join the Study ofExtended Cosmic-Ray Air Showers

Gregory SnowDepartment of Physics and Astronomy

University of NebraskaLincoln, Nebraska, USA

University of Washington Physics Department ColloquiumSeattle, WashingtonNovember 27, 2000

Outline

• Introduction to Extended Cosmic-Ray Air Showers

• Overview of present and planned ground-based arrays

• CROP in Nebraska

• Other cosmic ray education/outreach projects

• The NALTA Consortium

• Conclusions

Specific Uses of the Internet

Data Analysis• Exchanging data sets to search for cosmic-ray time coincidences based on GPS time stamp• Downloading, file management, running physics analysis programs, statistics, probability, reporting results

Technical info for installation/operation at remote schools• Step-by-step instructions, troubleshooting, frequently asked questions• Crucial for expanding CROP around remote hubs

High school curriculum lessons and supplements• Level-appropriate presentations, references, useful links

E-mail communication with project leaders• Workshop organization• Status at the school• Specific problems to solve

Informal communication among participants• “Last night we recorded an energetic shower! Did you see one?”

High Energy Cosmic Raysand

The Cosmic Ray Observatory Project (CROP)Gregory Snow

Department of Physics and AstronomyUniversity of Nebraska

Lincoln, Nebraska, USA

West Point High SchoolWest Point, Nebraska

October 16, 2000

Outline

• Cosmic rays and extended air showers

• The Pierre Auger Project and similar experiments

• CROP in Nebraska

• Other cosmic ray education/outreach projects

• Conclusions

http://www.physics.unl.edu/research/crop/crop.html

Education, Outreach, Public RelationsUpdate

PAO Collaboration MeetingNovember 13-17, 2000

Gregory SnowDepartment of Physics and Astronomy

University of NebraskaLincoln, Nebraska, USA

• Malargüe 50th Anniversary parade• Thursday, 11:00 a.m.

• Auger Central Campus Open House• Thursday, 19:30 - 21:30

• School visits in Malargüe

• Other talks

• Spanish “Cosmic Bullets”

• Update on high-school cosmic-ray projects• CROP and NALTA consortium

• A.O.B.

Spanish Translation of “Cosmic Bullets”

• Information from Arturo Fernández• “Ballas Cósmicas”• First printing 1000 copies• Revert Publishing Company

Curriculum Development

• CROP NSF grant disallows expenditures on curriculum development

• Separate proposal for curriculum developer• Refine “scientist” modules• Level-appropriateness• Science standards

• Work with teachers, students, local science coordinators, CROP Advisory Panel

• CROP basing curriculum modules around lecture and lab topics from 2000 Summer Workshop

• Teachers have expresses interest in varied uses of curriculum materials

• One-two weeks of cosmic rays, detectors, and CROP in physics class

• Short overview for physics class if only small groupor science club really participates in CROP work

• One month min-courses between semesters

Topics Available Now inDraft Form

Lab Curriculum• Polishing, cleaning scintillator• Gluing PMT and wrapping scintillator• Assembling high-voltage supply• Oscilloscope lesson• Turning on counters, source tests, finding/fixing light leaks• Measure counter efficiency, high voltage plateau

Class Curriculum• History of cosmic rays• Interaction of charged particles with matter• Scintillators and photomultiplier tubes• Cosmic ray energy spectrum• Julian calendar, UTM, galactic coordinates• Global positioning system• Ionizing particle detectors• Calorimeters and showering• Particle zoo and the Standard Model• Tour of high-energy particle accelerators• Random events, probability• Monte Carlo simulations• Lightning protection

Workshop on Cosmic Ray Physics withSchool-Based Detector Networks

University of Washington/SeattleSeptember 21-23, 2000

http://www.phys.washington.edu/~walta/NALTA.html

Many thanks to Jeff Wilkes, the WALTA team,and UW for hosting this workshop!