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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, electrons and photons at Earth’s surface. A map of the northern Pierre Auger detector site in Millard County, Utah.
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Development of Giant Air Shower in Earth’s Atmosphere Primary cosmic ray Mostly muons, electrons and 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 galactic nucleus
Possible Source of Concident, Widely-Separated Showers: the GZ Effect (Gerasimova-Zatsepin) Cosmic ray iron nucleus Optical photon from the sun Nuclear fragments from photo-disintegration Earth’s Surface • 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 particle detectors 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.
How a cosmic-ray air shower is formed and detected Primary cosmic ray (mostly protons) impinges 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 arriving secondaries • Number of secondaries related to primary cosmic ray energy • Relative arrival time of secondaries tells incident direction
“Air shower” of secondary particles formed by collisions with air molecules How a cosmic-ray air shower is formed and detected Primary cosmic ray (mostly protons or light nuclei) impinges on earth’s atmosphere from outer space Grid of particle detectors intercept and sample portion of arriving secondaries • Number of secondaries related to primary cosmic ray energy • Relative arrival time of secondaries tells incident direction
Counties and Congressional Districts in Nebraska
CASA counter Cosmic ray detector inside each enclosure Weather-proof detector enclosures GPS receiver Cables bring signals to PC Photomultiplier tube PC inside classroom 24” Plastic scintillator 24” 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
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, Nebraska USA Gregory Snow and Daniel Claes Principal Investigators A Model for Pierre Auger Education and Outreach • 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
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)
250 miles CROP Cosmic Ray Observatory Project 450 miles • A high-school based mini-Pierre Auger Project • Coarser array covering much larger area
The KASCADE experiment in Karlsruhe, Germany
The Cosmic Ray Observatory Project (CROP) University of Nebraska Lincoln, Nebraska USA Gregory Snow and Daniel Claes Principal 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 CROP Stacks of scintillator pieces without photomultiplier tubes
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
Inventory of Equipment from 1999 Recovery Trip to Chicago Air Shower Array Dugway Proving Grounds, Utah • 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 to equip >20 schools
Utah Argentina Detector Sites James Cronin (Univ. Chicago) and Alan Watson (Univ. Leeds) Project Spokespersons
The Pierre Auger Observatory uses 1600 particle detectors 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 experiment in Karlsruhe, Germany
Fluorescence Detectors Fly’s Eye II Dugway, Utah High-Res Experiment Dugway, Utah
Other Cosmic Ray Outreach Projects • 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. • 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 Map Surrounding Edmonton, Alberta, Canada
Refrigerator cold CO2 bubble (887 mph) 0.02 eV Room temperature nitrogen N2 (1160 mph) 0.03 eV Atoms in sun’s MILLION DEGREE surface 0.50 eV Energy given to each single electron when accelerated by AA battery 1.5 eV Electrons accelerated by your television picture tube (traveling ~1/3 speed of light) 30,000 eV Fermi National Lab’s high energy protons 1,000,000,000,000 eV
Recall: 1 joule = 6.2 x 1018 eV Superball bounced over your house 4 x 1017 eV Pitched baseball4 x 1020 eV Slammed hockey puck 1 x 1021 eV The highest energy Cosmic Rays are SUBATOMIC particles carrying the energy of MACROSCOPIC objects! 4 x 1021 eV = 60 joules
The Cosmic Ray Energy Spectrum FERMILAB’s protons Bounced Superball Pitched baseball Hockey Puck
The Akeno Giant Air Shower Array (AGASA) in Japan Primary energy 2 1020 eV • 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
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 Rays The Pierre Auger Project and The Cosmic Ray Observatory Project (CROP) Gregory Snow Department of Physics and Astronomy University of Nebraska Lincoln, Nebraska, USA • 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.org http://www.physics.unl.edu/research/crop/crop.html Lincoln International School Buenos Aires, Argentina April 10, 2000
High Energy Cosmic Rays and The Cosmic Ray Observatory Project (CROP) Gregory Snow Department of Physics and Astronomy University of Nebraska Lincoln, Nebraska, USA • 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 Northeastern University Boston, MA April 26, 2000