radiation

Table of Contents

Introduction
General background
- Types of radiation
  - Electromagnetic rays and neutrinos
    - Visible light and the other components of the electromagnetic spectrum
    - Neutrinos and antineutrinos
  - Matter rays
- The structure and properties of matter
- The effects of radiation
Fundamental processes involved in the interaction of radiation with matter
- The passage of electromagnetic rays
  - The field concept
  - Frequency range
  - Properties of light
  - Wave aspects of light
    - Double refraction
    - Dispersion
  - Electromagnetic waves and atomic structure
    - Quantum concepts
    - Absorption and emission
  - Particle aspects of light
    - The photoelectric effect
    - Cross section and Compton scattering
    - Pair production
    - X rays and gamma rays
- The passage of matter rays
  - Heavy charged particles
    - Linear energy transfer and track structure
    - Stopping power
    - Range
  - Electrons
    - Cherenkov radiation
    - Energy-transfer mechanism
  - Neutrons
Secondary effects of radiation
- Purely physical effects
- Molecular activation
  - Luminescence
  - Ionization phenomena
  - Excitation states
  - Energy transfer
    - Fluorescence and phosphorescence
    - Photographic process
- Ionization and chemical change
  - Photochemistry
  - Radiation chemistry
    - Radiation chemical reactions
    - Symbolism of radiation chemistry
    - Time scales in radiation chemistry
Tertiary effects of radiation on materials
- Heating effects
- Crystal-lattice effects
- Surface effects
Biological effects of ionizing radiation
- Historical background
- Units for measuring ionizing radiation
- Sources and levels of radiation in the environment
  - Natural sources
  - Artificial sources
- Mechanism of biologic action
- Radionuclides and radioactive fallout
  - Accumulation in critical organs
  - The hazards of long-lived radioisotopes
- Major types of radiation injury
  - Effects on the cell
    - Damage to genes (mutations)
    - Damage to chromosomes
  - Effects on organs of the body (somatic effects)
    - Skin
    - Bone marrow
    - Gastrointestinal tract
    - Reproductive organs
    - Lens of the eye
    - Brain and sensory organs
    - Radiation sickness
  - Effects on the growth and development of the embryo
  - Effects on the incidence of cancer
  - Shortening of the life span
- Protection against external radiation
- Control of radiation risks
Biologic effects of non-ionizing radiation
- Effects of Hertzian waves and infrared rays
  - Hertzian waves
  - Infrared rays
- Effects of visible and ultraviolet light
  - Intrinsic action
  - Photodynamic action
  - Effects on development and biologic rhythms
  - Effects on the eyes
Applications of radiation
- Medical applications
  - Imaging techniques
    - X-ray systems
    - Positron emission tomography (PET)
    - Nuclear magnetic resonance (NMR) imaging
  - Other radiation-based medical procedures
    - Radionuclides in diagnosis
    - Treating cancer and other diseases with highly energetic forms of ionizing radiation
    - Ultraviolet radiation therapy
    - Phototherapy
    - Treatment with lasers
    - Diathermy
- Applications in science and industry
  - Photochemistry
  - High-energy radiation
  - Lasers

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Key People

Becquerel, Henri

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French physicist

David Hilbert

David Hilbert

German mathematician

Robert H. Dicke

American physicist

Chandrasekhar, Subrahmanyan

Subrahmanyan Chandrasekhar

American astronomer

Georges Charpak

Georges Charpak

French physicist

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C.T.R. Wilson, 1927

C.T.R. Wilson

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