3/2003 Rev 1 I.2.9 – slide 1 of 35 Session I.2.9 Part I Review of Fundamentals Module 2Basic Physics and Mathematics Used in Radiation Protection Session 9Nuclear Reactions IAEA Post Graduate Educational Course Radiation Protection and Safety of Radiation Sources

3/2003 Rev 1 I.2.9 – slide 2 of 35 Various examples of nuclear reactions will be discussed Various examples of nuclear reactions will be discussed Students will learn about properties of neutrons, nuclear decay processes, cross section, neutron interactions, and various kinds of nuclear reactions including charged particle reactions, spallation, fission and fusion reactions Students will learn about properties of neutrons, nuclear decay processes, cross section, neutron interactions, and various kinds of nuclear reactions including charged particle reactions, spallation, fission and fusion reactions Introduction

3/2003 Rev 1 I.2.9 – slide 3 of 35 Content Properties of neutrons Properties of neutrons Nuclear decay processes Nuclear decay processes Cross section Cross section Neutron interactions Neutron interactions Charged particle reactions Charged particle reactions Spallation Spallation Fission Fission Fusion Fusion

3/2003 Rev 1 I.2.9 – slide 4 of 35 Overview Various kinds of nuclear reactions will be discussed and examples shown Various kinds of nuclear reactions will be discussed and examples shown Health physics significance and energy considerations of nuclear reactions will be discussed Health physics significance and energy considerations of nuclear reactions will be discussed

3/2003 Rev 1 I.2.9 – slide 5 of 35 Chadwick, 1932, alpha bombardment He + Be C + n + Q Neutron Discovery Neutron Discovery Thermal ( eV) Slow ( eV) Epithermal (100 eV – 100 keV) Fast (100 keV – 1 MeV) Ultrafast (>1 MeV) Neutron Classification Neutron Classification Properties of Neutrons

3/2003 Rev 1 I.2.9 – slide 6 of 35 Neutron Characteristics Neutron Characteristics symbol - n symbol - n no charge no charge rest energy MeV rest energy MeV has a magnetic moment has a magnetic moment it is a fermion it is a fermion Neutron Interaction with matter Neutron Interaction with matter Scattering (2 mechanisms) Scattering (2 mechanisms) Absorption (>4 mechanisms) Absorption (>4 mechanisms) Properties of Neutrons

3/2003 Rev 1 I.2.9 – slide 7 of 35 Nuclear Reactions Nuclear Decay

3/2003 Rev 1 I.2.9 – slide 8 of 35 Nuclear Reactions Alpha Decay

3/2003 Rev 1 I.2.9 – slide 9 of 35 Nuclear Reactions Beta Decay

3/2003 Rev 1 I.2.9 – slide 10 of 35 Nuclear Reactions Positron Decay or Electron Capture Electron Capture Electron Capture Positron Emission

3/2003 Rev 1 I.2.9 – slide 11 of 35 Nuclear Reactions Summary of Major Decay Mechanisms

3/2003 Rev 1 I.2.9 – slide 12 of 35 Cross Section where = cross section = cross section R = number of reactions per unit time per nucleus I = number of incident particles per unit time per unit area = =RI

3/2003 Rev 1 I.2.9 – slide 13 of 35 Nuclear Reactions Fast Neutron Interactions Elastic scattering - neutrons interact with particles of approximately the same mass such as protons (billiard ball analogy) Elastic scattering - neutrons interact with particles of approximately the same mass such as protons (billiard ball analogy) Occurs in materials rich in hydrogen such as water, wax, concrete Occurs in materials rich in hydrogen such as water, wax, concrete Accounts for about 80% of fast neutron dose to tissue Accounts for about 80% of fast neutron dose to tissue

3/2003 Rev 1 I.2.9 – slide 14 of 35 Inelastic scattering – neutrons interact with particles of much greater mass, for example, iron (table tennis ball vs bowling ball analogy) Inelastic scattering – neutrons interact with particles of much greater mass, for example, iron (table tennis ball vs bowling ball analogy) Nuclear Reactions Fast Neutron Interactions

3/2003 Rev 1 I.2.9 – slide 15 of 35 Nuclear Reactions Elastic Scattering of Neutrons

3/2003 Rev 1 I.2.9 – slide 16 of 35 Nuclear Reactions Inelastic Scattering of Neutrons

3/2003 Rev 1 I.2.9 – slide 17 of 35 Neutron Reactions (n, CP) (n, gamma) (n, fission)

3/2003 Rev 1 I.2.9 – slide 18 of 35 Nuclear Reactions Neutron Absorption, Charged Particle n + 10 B 7 Li(*) + n + 10 B 7 Li(*) + 7 Li(*) 7 Li + soft gamma (480 KeV)

3/2003 Rev 1 I.2.9 – slide 19 of 35 Fission

3/2003 Rev 1 I.2.9 – slide 20 of 35 Breeding 239 Pu from 238 U Neutron Capture

3/2003 Rev 1 I.2.9 – slide 21 of 35 Details of 239 U Decay to 239 Pu 239 U (23.5 min) 239 Np (2.3 d) 239 Pu

3/2003 Rev 1 I.2.9 – slide 22 of 35 Nuclear Reactions Charged Particle Bombardment p + 68 Zn 67 Ga + 2n + 16 O 18 F + p + n + 16 O 18 F + p + n

3/2003 Rev 1 I.2.9 – slide 23 of 35 Nuclear Reactions Spallation

3/2003 Rev 1 I.2.9 – slide 24 of 35 Spallation Products

3/2003 Rev 1 I.2.9 – slide 25 of 35 Spallation Produced by Neutrons or Protons

3/2003 Rev 1 I.2.9 – slide 26 of 35 Nuclear Fusion Reactions Utilize Isotopes of Hydrogen

3/2003 Rev 1 I.2.9 – slide 27 of 35 Nuclear Reactions Fusion

3/2003 Rev 1 I.2.9 – slide 28 of 35 Deuteron – Deuteron Fusion

3/2003 Rev 1 I.2.9 – slide 29 of 35 Tritium – Proton Production from Fusion

3/2003 Rev 1 I.2.9 – slide 30 of 35 3 He with Neutron Production from Fusion

3/2003 Rev 1 I.2.9 – slide 31 of 35 Fusion - Tokamak

3/2003 Rev 1 I.2.9 – slide 32 of 35 Energy Production Reactions in Stars

3/2003 Rev 1 I.2.9 – slide 33 of 35 CNO Energy Production Reactions in Stars

3/2003 Rev 1 I.2.9 – slide 34 of 35 Summary Various examples of nuclear reactions were discussed Various examples of nuclear reactions were discussed Students learned about properties of neutrons, nuclear decay processes, cross section, neutron interactions, and various kinds of nuclear reactions including charged particle reactions, spallation, fission and fusion Students learned about properties of neutrons, nuclear decay processes, cross section, neutron interactions, and various kinds of nuclear reactions including charged particle reactions, spallation, fission and fusion

3/2003 Rev 1 I.2.9 – slide 35 of 35 Where to Get More Information Cember, H., Johnson, T. E., Introduction to Health Physics, 4 th Edition, McGraw-Hill, New York (2008) Cember, H., Johnson, T. E., Introduction to Health Physics, 4 th Edition, McGraw-Hill, New York (2008) Martin, A., Harbison, S. A., Beach, K., Cole, P., An Introduction to Radiation Protection, 6 th Edition, Hodder Arnold, London (2012) Martin, A., Harbison, S. A., Beach, K., Cole, P., An Introduction to Radiation Protection, 6 th Edition, Hodder Arnold, London (2012) Jelley, N. A., Fundamentals of Nuclear Physics, Cambridge University Press, Cambridge (1990) Jelley, N. A., Fundamentals of Nuclear Physics, Cambridge University Press, Cambridge (1990) Firestone, R.B., Baglin, C.M., Frank-Chu, S.Y., Eds., Table of Isotopes (8 th Edition, 1999 update), Wiley, New York (1999) Firestone, R.B., Baglin, C.M., Frank-Chu, S.Y., Eds., Table of Isotopes (8 th Edition, 1999 update), Wiley, New York (1999)