1. Jim Hartnett PHYS 3305 Radioactive Decay - Jim Hartnett1

2.  What is it?  Macroscopic Effects  Types of Decay  The Decay Chain  Fission Radioactive Decay - Jim Hartnett2

3.  A nucleus may be bound in a relatively high energy state, and if it can attain a lower energy, it will eventually do so.  Radioactive isotopes  Emission of particles reduces state Radioactive Decay - Jim Hartnett3

4.  Half life  Ionizing Radiation ◦ Molecular bonds ◦ Effects on electrons in substances  Geiger counters  Smoke detectors ◦ Effects on health Radioactive Decay - Jim Hartnett4

5.  Elements can have both stable and unstable forms, natural and artificial  Examples: ◦ Uranium (all isotopes, natural) ◦ Plutonium (all isotopes, natural/artificial) ◦ Potassium ( 40 K, natural) Radioactive Decay - Jim Hartnett5

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7.  Three types ◦ Electron Emission ◦ Electron Capture  photon emission  Usually X-Ray spectrum ◦ Positron emission  Short living  Annihilation reaction  Two Gamma photons Radioactive Decay - Jim Hartnett7

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11.  High energy photon release ◦ Lowers energy state ◦ Mass and atomic numbers? Radioactive Decay - Jim Hartnett11 Image: http://ie.lbl.gov/radioactivedecay/page.htm

12.  Not emitted without trigger ◦ Spontaneous fission ◦ Alpha particle interactions ◦ High energy photon capture  No charge ◦ Greater penetration ◦ Indirectly ionizes materials Radioactive Decay - Jim Hartnett12

13. Radioactive Decay - Jim Hartnett13 Illustrates lifecycle of radioisotope

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15.  Splitting atoms ◦ Isotopes considered fissile ◦ Occurs in some natural conditions Radioactive Decay - Jim Hartnett 15

16.  Lowering of unstable states  Ionizing radiation (direct and indirect)  Useful effects ◦ Power, medicine, transmutation  Dangers ◦ Radiation poisoning, undesired activation Radioactive Decay - Jim Hartnett16

17. 1. Harris, Randy, and Randy Harris. Modern Physics. Second ed. San Francisco: Pearson/Addison Wesley, 2008. 2. "Radiation Basics." Nuclear Regulatory Commission. October 17, 2014. Accessed December 1, 2014. http://www.nrc.gov/about- nrc/radiation/health-effects/radiation-basics.html.http://www.nrc.gov/about- nrc/radiation/health-effects/radiation-basics.html 3. "Radiation and Its Health Effects." Nuclear Regulatory Commission. October 17, 2014. Accessed December 1, 2014. http://www.nrc.gov/about-nrc/radiation/rad-health-effects.html. http://www.nrc.gov/about-nrc/radiation/rad-health-effects.html 4. Steinberg, Ellis. "Nuclear Fission (physics)." Encyclopedia Britannica Online. Accessed December 1, 2014. http://www.britannica.com/EBchecked/topic/421629/nuclear- fission. http://www.britannica.com/EBchecked/topic/421629/nuclear- fission 5. "Nuclear Chemistry." Radioactive Decay. Accessed December 1, 2014. http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch23/ modes.php. http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch23/ modes.php Radioactive Decay - Jim Hartnett17