(EMR) Electromagnetic radiation consists of an electric and a magnetic field component. All EMR travels in a vacuum at the speed of light. EMR is classified related to the frequency//length of the wave.
An EM wave consists of discrete packets of energy, named photons (quantization). The energy of the photons depends on the frequency of the wave. Planck-Einstein equation:
E = h * f
E (energy); h (Planck's constant); f (frequency)
EMR types include in order of increasing frequency//decreasing wavelength: radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays and gamma rays. EMR contains energy and momentum, which may be imparted when it interacts with matter.

See Gamma Radiation.

Ion particles accelerated in a cyclotron are diverted by a magnetic field to a circular course until a desired energy is reached. The ion beam resulting from this procedure is e.g. used for the production of radionuclides.

See also Ion, Cyclotron.

Magnetic flux density is the amount of magnetic flux per unit area of a section, perpendicular to the direction of flux. The magnetic flux density is the product of the magnetic field strength and permeability. The SI unit for flux density is weber per square meter. One weber per square meter equals one tesla (T).

Magnetic permeability is the degree of magnetization of a material that responds linearly to an applied magnetic field. The SI units of permeability are henry per meter (H/m) or newton per square ampere (N/A²).

The near field is one of the boundary regions to classify characteristics of electromagnetic fields as a function of distance from the radiating source. The variation of the electromagnetic wave is usually more rapid in the near field than in the far field.