Covers essential physics concepts for understanding and calculating problems in the physical energy deposited in matter from ionizing radiation. The focus of application is on medical uses, both imaging and radiation therapy. There is more weight on radiation therapy throughout the book because of the much greater need for accuracy and precision in that field. Modern protocols can guide a person toward uncertainties of only 0.5% in the energy deposited per unit mass, the dose. In order to achieve this remarkably low level of uncertainty, one must fully understand all of the subtleties along the way. That is the purpose of this book. The aim of this work is to provide a deep understanding of all the pieces that underlie these practical protocols, and not to teach one how to use these protocols. It should be of interest to those who already have a basic education in this field, but who wish to expand and deepen their knowledge without all of the overhead of a large textbook. The information contained herein provides a more intuitive grasp of the physics concepts used in radiation dosimetry in medical applications, especially, but not limited to, radiation therapy physics.

Table of Contents:
1. Ionizing Radiation and What It Does in the Body References 2. Radiation Fields and Their Statistics Fluence and Fluence Rate Energy Fluence and Energy Fluence Rate Angular Distributions Energy Distributions References 3. Photon Interactions Cross Sections and the Attenuation Coefficient Terma, Kerma, and Collision Kerma Dose Definition Narrow and Broad Beam Geometry of Photons References 4. Photoelectric Effect Differential Cross Section for Photoelectric Effect (K-shell) Fluorescent Photons and Auger Electrons Mass Energy Transfer Coefficient for the Photoelectric Effect References 5. Compton Scattering Effect Differential Cross Section for Compton Effect Differential Cross Section Relative to Recoil Electron Energy Mass Energy Transfer Coefficient for the Compton Effect Binding Energy Correction for the Klein-Nishina Cross Section References 6. Pair (and Triplet) Production Effect Pair Production Cross Section for Pair Production The Similarity between Pair Production and Bremsstrahlung Triplet Production The Triplet Production Cross Section Positron Annihilation in Flight References 7. Other Photon Interactions and Summary Rayleigh (Coherent) Scattering Photonuclear Interactions Relative Importance of Each Interaction Type Total Cross Sections (or Coefficients) Cross Sections for Compounds and Mixtures References 8. Charged Particle Interactions with Matter Interactions of Heavy Charged Particles Stopping Power and Mass Stopping Power Collisional Mass Stopping Power for Heavy Charged Particles Soft Collision Mass Stopping Power for Heavy Charged Particles Hard Collision Mass Stopping Power for Heavy Charged Particles Shell Correction Dependence of the Stopping Power on the Medium Mass Collisional Stopping Power Dependence on Particle Velocity Mass Collisional Stopping Power Dependence on Particle Charge Electron and Positron Interactions Mass Collision Stopping Power for Electrons and Positrons Polarization or Density Effect Correction Restricted Mass Stopping Power Linear Energy Transfer and Unrestricted Linear Energy Transfer Mass Radiative Stopping Power Radiation Length Radiation Yield Elastic Scattering Multiple Scattering Particle Range Calculating the CSDA Range Projected Range Practical Range References 9. Radiation Equilibrium Fano's Theorem Charged Particle Equilibrium Exposure Transient Charged Particle Equilibrium References 85 10. Absorbed Dose in Media Containing Radioactive Materials Radioactive Decay Alpha Decay Alpha Decay Specific to Dosimetry Dose Rate Calculations for Alpha Decay Beta Decay Beta Decay Specific to Dosimetry Fermi Theory of Beta Decay Electron Capture (EC) Dose Rate Calculations for Beta Decays and Electron Capture Gamma Decay Internal Conversion Some Essential Gamma Decay Theory Absorbed Fraction (AF) Dose Rate Calculations for Gamma Decay and Internal Conversion General Dose Rate Calculations References 11. Dose from Directly Ionizing External Radiation Sources Dose in Thin Films 1. Dose in Thin Films When d -ray CPE Exists 2. Dose in Thin Films When d-ray CPE Does Not Exist Average Dose in Thick Foils 1. Average Dose in Very Thick Foils from Electrons 2. Average Dose in Thick Foils from Heavy Charged Particles 3. Average Dose in Thick Foils from Electrons Dose When the Electron Energy Spectrum is Known References 12. Dosimetry Introduction Characteristics of Dosimeters 1. Precision or/vs. Accuracy 2. Dose Sensitivity 3. Stability 4. Energy Dependence 5. Angular Dependence Ion Chamber Dosimetry Cavity Theory 1. Bragg-Gray Cavity Theory 2. Spencer-Attix Cavity Theory 3. Other Cavity Theories for Photon Beams Cavity Theory Examples and Discussion Dosimetry Fundamentals Advantages of Media Matching References 13. Cavity Ionization Chambers, Circuits, and Corrections Thimble-type Chambers Condenser-type Chambers Parallel Plate Chambers Charge and Current Measurements Charge Measurement Specifics Current Measurement Specifics Density and Humidity Corrections to an Ideal Ion Chamber Ion Chamber Saturation and Recombination References 14. Calibration of Ion Chambers and Photon Beams Understanding TG-21 at the NIST Calibration Lab (ADCL) Understanding TG-21 at the Clinic Calibration of Electron Beams Updated Calibration Protocol for Medical Photon Beams (TG-51) A Few Key Concepts for TG-51 Calibration References