ABSTRACT
CONTENTS 8.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432 8.2 Interaction of Radiation with Matter: Photons . . . . . . . . . . . . . . . . 434
8.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 434 8.2.2 Cross Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 435 8.2.3 Compton Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 437 8.2.4 Thompson Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 438 8.2.5 Klein-Nishina Cross Section for the Compton Effect . . . . . . 439 8.2.6 Corrections of the Bonding Energy of the Electrons . . . . . . . 440 8.2.7 The Photoelectric Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442 8.2.8 Pair Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443 8.2.9 Rayleigh Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 443 8.2.10 Photonuclear Interaction . . . . . . . . . . . . . . . . . . . . . . . . . . . 444 8.2.11 Interaction Coefficients . . . . . . . . . . . . . . . . . . . . . . . . . . . . 444
8.3 Interaction of Radiation with Matter: The Electrons . . . . . . . . . . . . 445 8.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445 8.3.2 Radiative Energy Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445 8.3.3 Loss of Energy by Collision . . . . . . . . . . . . . . . . . . . . . . . . . 446 8.3.4 Stopping Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 446 8.3.5 Linear Energy Transfer, LΔ, LET . . . . . . . . . . . . . . . . . . . . . 447 8.3.6 Range and CSDA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447 8.3.7 Mean Energy Spent per Ion Pair Produced, W . . . . . . . . . . . 448
8.4 Radiation Dosimetry Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . 448 8.5 Radiation Protection Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 8.6 Quality Factor, Weighting Factors, and Relative Biological
Effectiveness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455 8.7 Energy Degradation in Matter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456 8.8 Monte Carlo Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 465 8.9 Conventional and Cellular Dosimetry for Radionuclides . . . . . . . . 467 8.10 Physics of the Biological Effects of Radiation . . . . . . . . . . . . . . . . . 474
8.10.1 The Cell as a Target of Ionizing Radiation . . . . . . . . . . . . . . 481 8.10.2 Composition, Shape, and Size . . . . . . . . . . . . . . . . . . . . . . . 481
8.11 Action Modes. Target Theory Models: Survival Curves . . . . . . . . . 483 8.11.1 Water Radiolysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 486 8.11.2 Effects in Aqueous Solutions . . . . . . . . . . . . . . . . . . . . . . . . 487 8.11.3 Ionizing Radiation, Ionization Mechanisms, and
Biological Action . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 488 8.12 Mathematical Models of Cellular Survival in Ionizing
Radiation Fields . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 494 8.12.1 Multiple Target Models (Target Theory Models) . . . . . . . . . . 495
8.12.1.1 One Sensitive Region n Hits . . . . . . . . . . . . . . . . . . 495 8.12.1.2 Multiple Sublethal Sensitive Zones/One-Hit
Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497 8.12.1.3 Mixed Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499 8.12.1.4 The Linear-Quadratic Model . . . . . . . . . . . . . . . . . 501 8.12.1.5 Comparison of the L-Q and Target
Theory Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504 8.13 Nontargeted Effects Complementary to Direct Action of
Ionizing Radiation for Low Doses . . . . . . . . . . . . . . . . . . . . . . . . . 505 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506
In living matter, atoms and molecules maintain their individual and collective configurations as a result of very specific energy interactions, which are subject to complex physical-chemical and biological rules. Living matter at all levels can be understood as a set of active processes that organize matter and energy within ordered complex systems.
