Electromagnetic beta particles

Gamma ray The shortest wavelength and highest energy type of all electromagnetic radiation. It originates in the nucleus of radioactive isotopes along with alpha particle, beta particle, or neutron emissions. 

Whereas Table 2 presents some radiation terms that are pertinent to the following discussion, Table 3 lists the radioisotopes and their half-lives that are suitable to microautoradiography. Of the two types of nuclear radiation, i.e., wavelike electromagnetic radiation (X-ray and gamma ray) and corpuscular radiation (electrons, beta particles, and alpha particles) the latter are the most employable for microautoradiography. The reader is referred to Slater (20) for in-depth discussion of all aspects of radiobiology. 

Three main forms of radioactive decay involve the emission of alpha particles, beta particles, and gamma rays. An alpha particle is equivalent to the nucleus of a helium atom. Beta particles are nothing more than electrons. Gamma rays are a form of electromagnetic radiation. 

The positron is the opposite of an electron. Unlike a beta particle, a positron seldom makes it into the surroundings. Instead, the positron usually collides with an electron, its antiparticle. Any time a particle collides with its antiparticle, all of the masses of the two particles are converted entirely into electromagnetic energy or gamma rays. This process is called annihilation of matter, which is illustrated in Figure 9. 

Composition Alpha particles Beta particles High-energy electromagnetic radiation... 

Radioactivity is a spontaneous nuclear transformation that results in the formation of a different element and, usually, the release of excess energy as particulate and/or electromagnetic radiation. For example, tritium transforms into He-3 and emits a beta particle. The activity of a sample is the rate of radioactive transformation and is usually symbolized by the letter A. In other words, the number of nuclear transformations occurring in a given time. There are two systems of units commonly used for radiological measurements the International System (SI) and the Traditional units. In SI units, activity is measured in bequerels (Bq) where 1 Bq = 1 transformation per second. In the traditional units, activity is measured in curies (Ci) where 1 Ci = 3.7 x 1010 transformation per second = 3.7 x 1010 Bq. The specific activity is defined as the activity of the... 

Beta particles are negatively charged and smaller, travel faster, and penetrate farther than alpha particles. A beta particle is 1/1800 the size of a proton, or roughly equal to an electron in mass (see Figure 9.5). Beta particles will penetrate the skin and travel from 3 to 100 ft. Full turnouts and SCBAs will not provide full protection from beta particles. Particulate radiation results in contamination of personnel and equipment where the particles come to rest. Electromagnetic energy waves, like gamma, do not cause contamination. 

Alpha particles Positively charged particles identical to helium-4 nuclei emitted by certain radioactive isotopes Beta particles Electrons ejected at high speeds from certain radioactive isotopes Gamma rays Eligh-energy electromagnetic radiation emitted from radioactive isotopes... 

Since gamma rays are electromagnetic waves, they are not charged and do not have any mass, they interact differently with matter than do alpha and beta particles, although the net effect is usually still ionization of an orbital electron. They interact with the electrons in matter... 

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