Page 137 - Radiochemistry and nuclear chemistry

CHAPTER 6

Absorption of Nuclear Radiation

Contents

6.1. Survey of absorption processes 125
6.2. Absorption curves 126
6.3. Absorption of protons and heavier ions 130
6.4. Absorption of electrons 134
6.4.1. Ionization 135
6.4.2. Bremsstrahlung 136
6.4.3. ~erenkov radiation 137
6.4.4. Positron annihilation 138
6.4.5. Absorption curves and scattering of ~particles 140
6.5. Absorption of -c-radiation 141
6.5.1. Attenuation coefficient 141
6.5.2. Partial absorption processes 142
6.6. Absorption of neutrons 147
6.7. Radiation shielding 147
6.8. Analytical applications of radiation absorption 149
6.8.1. SIMS (Secondary Ion Mass Spectrometry) 150
6.8.2. PIXE (Proton or Particle Induced X-ray Emission) 150
6.8.3. ESCA (Electron Spectrometry for Chemical Analysis) 152
6.8.4. XFS (X-ray Fluorescence Spectrometry) 152
6.8.5. M/~ssbauer effect 154
6.9. Technical applications of radiation sources 157
6.9.1. Radionuclide gauges 158
6.9.2. Radiography 161
6.9.3. Radionuclide power generators 162
6.10. Exercises 163
6.11. Literature 165

Our understanding of the nature of nuclear particles is based on their mode of interaction
with matter. Knowledge about this interaction is essential in a variety of areas of nuclear
science, such as the proper utilization and construction of detection and measuring devices
for radiation, the design of radiation shielding, the medical and biological applications of
radiation, radiochemical synthesis, etc.
The term nuclear radiation is used to include all elementary particles, both uncharged
(e.g. photons) and charged, having energies in excess of approximately 100 eV whether the
particles have been produced through nuclear reactions (spontaneous or induced) or have
acquired their energy in electrostatic accelerators. This lower energy limit is very high in

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