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Rob Hewitt, Robyn Reist, Jason Sadowski Engineering Physics College of Engineering Student Paper Presentation Competition March 26, 2009 Supervisors: Mike Bradley, Chary Rangacharyulu Client: Tyson Pederson (Areva). Uranium Ore Analysis. Outline. Overview/definition of project
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Rob Hewitt, Robyn Reist, Jason Sadowski Engineering Physics College of Engineering Student Paper Presentation Competition March 26, 2009 Supervisors: Mike Bradley, Chary Rangacharyulu Client: Tyson Pederson (Areva) Uranium Ore Analysis
Outline • Overview/definition of project • Introduction to 238U spectrum and decay chain • How to determine abundance of 238U • Apparatus • Simplified calculations • Software • Simulated demonstration • Wrap-up/future goals
Overview of Project • Uranium ore analysis system for Areva • Currently only measure total radiation • System is needed to determine percentage of uranium in an ore sample • To be used by technicians on-site or in the lab • Defined project according to given constraints: Determine abundance of 238U in a sample using the most accurate, user friendly, and cost effective system.
Uranium Decay and Spectrum 101 • Radioactive isotopes decay into other elements by alpha and beta decay and give off gamma ray photons • Looking for 238U • Separate out 235U or create 239Pu (239U -> 239Np -> 239Pu) • Need to look further down chain • Measure the gamma energy given off by these isotopes
238U Decay Chain and Spectrum 295 keV 609 keV 352 keV Junk Energy, keV Stable
What to expect from 1g Uranium? • Described by 14 equations • Each decay has probability of gamma ray emission 238U 4.468x109 Yrs 234Th 24 days
What to expect from 1g Uranium? 214Bi (609 keV) 5.8x103 photons/s
Testing Apparatus Built for Specific Detector Fixed Geometry Adjustable Ruler Specific Rock Sizes Bulky Sealed Sample Holders
How do we convert a spectrum to useful information? Correct for detector efficiency and sample geometry Example (using one peak): We know 1g natural U emits 5.8x103 photons/s at 609 keV We have a 20 g sample and measure 10x103 photons/s in the 609 keV line This peak indicates 8.62% Uranium
Wrap-Up • Goals: • Accurate • Cost-effective • User friendly (automated and portable) • Next step: detailed documentation
Summary • Project overview • 238U introduction/Detecting gamma rays • Detector types and testing apparatus • Calculating percentage 238U • Software • Demonstration • Met goals, now documenting