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Summer 2013. G amma R ay A strophysics at N otre D ame. Project GRAND (Gamma Ray Astrophysics at Notre Dame). Calvin Swartzendruber Bethany Christian Schools, Goshen. With: Dr. J. Poirer, PI, Notre Dame Physics Department Susan Sakimoto, RET, Riley High School
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Summer 2013 Gamma RayAstrophysicsat Notre Dame
Project GRAND(Gamma Ray Astrophysics at Notre Dame) Calvin Swartzendruber Bethany Christian Schools, Goshen With: Dr. J. Poirer, PI, Notre Dame Physics Department Susan Sakimoto, RET, Riley High School Courtney Meyer, REHS, La Lumiere School Delmar Oropeza, REHS, Elkhart Memorial High School
Project GRAND(Gamma Ray Astrophysics at Notre Dame) Dr. Susan Sakimoto Riley High School, South Bend With: Dr. J. Poirer, PI, Notre Dame Physics Department Calvin Swartzendruber, RET, Bethany Christian Schools Courtney Meyer, REHS, La Lumiere School Delmar Oropeza, REHS, Elkhart Memorial High School
Project GRAND View from the Southern boundary (from Google Map street view)
The Inside Look of a Hut : Dehumidifier Amp Boards Wire Chambers Station Electronics Board Heater
Hut Vertical Cross-section and Schematic of Tracks • Hut Photo • Hut Cross section • Schematic of Tracks • absorption • deflection • shower • muon
Shower Experiment Single Muon Experiment >100 TeV >10 GeV 1 Hz 1800 Hz When at least 4 huts in coincidence, all 40,960 wires read and recorded. All single tracks are recorded 800 times per second.
Atmospheric Production of Muons Cosmic Ray impact on nucleus Pions p+ p- decay of pions muons (and neutrinos) muon half-life = 2.2 microseconds. At the speed of light, range = 660 m. Relativistic effects increase the range m n
What does Project GRAND Do? Project GRAND is an extensive air shower array which detects secondary muons. Project GRAND’s ability to identify the direction of origin for a muon track at a precise time allows for the creation of a map in right ascension and declination.
Forbush Event • A Forbush event is a rapid decrease in galactic cosmic ray counts after a coronal mass ejection (CME). • The magnetic field of the solar wind prevents some of the galactic cosmic rays from reaching Earth. • Named after Scott Forbush, who studied cosmic rays in the 1930’s-’40’s Oulu 2011 data
Series of Forbush Events with Ground Level Event Effects Figure from Yu.V.Balabin, Polar Geophysical Institute, Russian Academy of sciences, Apatity, Russia
GRAND data, 2003 Forbush Decrease Data corrected for pressure and efficiency 1st step (shock) 2nd step (ejecta) GLE effect Data from "Status Report on Project GRAND", J. Poirier, C. D'Andrea, C. Barry, T. Catanach, L. Cheng, T. Wilson and C. Swartzendruber, Proc 32nd ICRC, (2011)
2006 Forbush Decrease: Neutron and Muon Detector Comparison • TERA, APTY, Kiel Neutron Monitors • GRAND Muon Count • Corrected for efficiency, not pressure) • Nagoya, Japan Muon Count (hr. ave) • (corrected for pressure and efficiency) • Bulgaria Muon Count (5 min.) • (corrected for pressure and efficiency)
2011 Forbush Decrease: Muon Detector Comparison • Oulu Neutron Monitor • GRAND Muon Count • (corrected for efficiency) • Nagoya, Japan Muon Count (hourly average) • (corrected for efficiency and pressure) • Yang Ba Jing, Tibet, Muon Count (hourly) • (corrected for efficiency and pressure) • Bulgaria Muon Count (5 min.) • (corrected for efficiency and pressure)
2012 Forbush Decrease: Muon Detector Comparison • Oulu Neutron Monitor • GRAND Muon Count • (corrected for efficiency) • Nagoya, Japan Muon Count (hourly average) • (corrected for efficiency and pressure) • Yang Ba Jing, Tibet, Muon Count (hourly) • (corrected for efficiency and pressure) • Bulgaria Muon Count (5 min.) • (corrected for efficiency and pressure) 3/3/2012 -3/23-2012
Forbush Data Analysis Conclusions • GRAND can “see” at least one past Forbush event when the data is corrected for pressure and efficiency • Other Muon detectors with pressure corrections (e.g. Nagoya, Bulgaria, Yang Ba Jing) sometimes “see” Forbush events. • Without a working pressure correction, the Forbush events are not apparent in GRAND data. • We need to fix the pressure correction routine.
Each hut needs: • Argon/CO2 gas
Each hut needs: • Argon/CO2 gas • High voltage • AC power • Clock signal
Each hut sends: • Data signal
Start fiducial • 640 wires • Stop fiducial • 656 bits/hut
On-line Status & Diagnostics http://www.nd.edu/~grand/live/
Humidity Heat Cold Wasps GRAND Lightning Lawnmowers Mice Groundhogs
Primary Roles: • All huts functional (fix/repair) • Improve experiment (more reliable) • Analyze data
Data Collection and Analysis Muon detector online data search Good hut correction data survey Data analysis for 2013 event request from Nagoya Supervised student data analysis Drafting new project slides Gas flow meter survey and data analysis Forbush decrease data analysis Hut Temperature and Humidity Experiment Maintenance Day to day hut troubleshooting/repair Ditch digging/electrical conduit installation (groundhog apparently chewed through the data cable) Filling in groundhog holes after capture to determine remaining population distribution Trailer cleaning/organization/safety update Barn roof repair Raccoon release Trailer Chemical Inventory and MSDS update Summer Projects
Accomplished - 2013 • Training & orientation for students • Troubleshooting bad huts... repaired as necessary • Safety Inspection • Fixed errors on TH and SE boards
Temperature and Humidity Data Logger • Future work includes comparing the hut data logger data with the temperature/humidity electronics boards
Accomplished - 2013 • Training & orientation for students • Troubleshooting bad huts... repaired as necessary • Safety Inspection • Fixed errors on TH and SE boards • Replaced buried data cables
Accomplished - 2013 • Training & orientation for students • Troubleshooting bad huts... repaired as necessary • Safety Inspection • Fixed errors on TH and SE boards • Replaced buried data cables • Calibrated Gas Flow Gauges