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GGamma amma RRayay
AAstrophysicsstrophysics
at at NNotre otre DDameame
Summer 2013Summer 2013
Project GRAND(Gamma Ray Astrophysics at Notre Dame)
Calvin Swartzendruber
Bethany Christian Schools, Goshen
With: Dr. J. Poirer, PI, Notre Dame Physics DepartmentSusan Sakimoto, RET, Riley High SchoolCourtney Meyer, REHS, La Lumiere SchoolDelmar 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 DepartmentCalvin Swartzendruber, RET, Bethany Christian SchoolsCourtney Meyer, REHS, La Lumiere SchoolDelmar Oropeza, REHS, Elkhart Memorial High School
Project GRAND View from the Southern boundary
(from Google Map street view)
The Inside Look of a Hut :
Proportional Wire Chamber
Hut Vertical Cross-section and Schematic of Tracks
• Hut Photo
• Hut Cross section
• Schematic of Tracks– absorption– deflection– shower– muon
>10 GeV>100 TeV
1800 Hz1 Hz
Shower Experiment Single Muon Experiment
All single tracks are recorded 800 times
per second.
When at least 4 huts in
coincidence, all 40,960 wires
read and recorded.
Atmospheric Production of Muons
decay of pions
impact on nucleus
Cosmic Ray
Pions
muon half-life = 2.2 microseconds. At the speed of light, range 660 m. Relativistic effects increase the range
muons (and
neutrinos)
Shower Experiment
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.
Coronal Mass Ejection (CME)
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
Classic Forbush Decrease
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
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)
Data corrected for pressure and efficiency
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
3/3/2012 -3/23-2012
• 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)
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
High Voltage & Clock Distribution
High Voltage & Clock Distribution
High Voltage & Clock Distribution
Clock Splitter & HV Dist. Box
Each hut sends:
• Data signal
• Start fiducial• 640 wires• Stop fiducial• 656 bits/hut
GRAND
Heat HumidityCold
Lightning
Mice
Groundhogs
Wasps
Lawnmowers
Primary Roles:
1. All huts functional (fix/repair)
2. Improve experiment (more reliable)
3. Analyze data
Summer Projects• 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
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
Flow Gauge Survey• According to the gas
flow meters, less than half the gas sent from the trailer reaches the huts.
• Is this an actual gas loss, or a flow meter problem?
Flow Gauge Testing
• Serial test of the flow meters (top right) shows that readings the 0.5 meters are routinely less than half of the 5.0 meter reading
• Parallel test shows that the sum of the four 0.5 meter readings are routinely less than half of the 5.0 meter reading.
• “Missing” Gas in the GRAND huts are probably a combination of flow meter discrepancies and small leaks.
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• Trapped ground hogs (and raccoons)
Future Work• Remote reading of pressure and
temperature in the huts
• Deploy Station Electronics Board v3
• Replace dead/shorted PWCs
• Troubleshoot huts
• Check and correct pressure correction software
• Weeds, moles, mice, etc.
Golf Cart Project
$1
A physicist A physicist
out out standing standing in his fieldin his field
Thanks for a GRAND Summer!