1. PHYS40422: Applied Nuclear Physics Paul Campbell Room 4.11 Paul.Campbell-3@manchester.ac.uk 1.Interaction of Radiation with Matter 2.Radiation Detection 3.Biological Effects of Radiation 4.Applications of Nuclear Techniques 5.Nuclear Fission 6.Nuclear Fusion http://personalpages.manchester.ac.uk/staff/Paul.Campbell-3/phys40422.htm

2. Chapter 1. The Interaction of Radiation with Matter : 1.2 Neutrons and gamma rays Neutrons – negligible EM interaction (bar weak magnetic). They stop via collisions… Elastic and inelastic possibilities.

4. The energy loss of neutrons in successive collisions

5. Nucleus  n to thermalise 1H 01.0018 2H 0.1110.72525 12C 0.7160.158115 238U 0.9830.00842200 n is the number of collisions to go from 2 MeV to a thermal energy of 0.025 eV Logarithmic Energy Decrement

6. From the collision kinematics we learn: In a light-mass medium the neutrons lose more energy on average in each collision. Each collision leads to big step changes in energy in a light-mass medium. It takes less collisions to reach thermal energies in a light-mass medium. In a heavy-mass medium the neutrons lose little energy on average in each collision. Each collision leads to small step changes in energy in a heavy-mass medium. It takes many collisions to reach thermal energies in a heavy-mass medium.

7. Some terminology Fast neutrons: E > ~ few MeV Slow neutrons: epithermal neutrons E ~ eV thermal neutrons E ~ 3/2 kT ~ 0.025 eV at room temperature

11. Klein-Nishina formula for Angular Distribution in Compton Scattering

12. Linear Attenuation Coefficient for Al

13. Linear Attenuation Coefficient for Pb K-shell Edge