Nowadays, three types of radiation are known : alpha, beta, gamma.
How are they formed?
All of the above types of radiation are the result of the decay process of isotopes of simple substances. Atoms of all elements consist of a nucleus and electrons that revolve around it. The nucleus is the smallest atom a hundred thousand times, but, thanks to its extremely high density, its mass is almost equal to the total mass of the entire atom. The nucleus contains positively charged particles - protons and neutrons that do not have an electric charge. Both those and others are interlinked very densely. By the number of protons in the nucleus they determine which chemical element the given atom belongs to, for example, - 1 proton in the nucleus is hydrogen, 8 protons - oxygen, 92 protons - uranium. The number of electrons in an atom corresponds to the number of protons in its nucleus. Each electron is characterized by a negative electric charge equal to the charge of the proton, for this reason the atom as a whole is neutral.
Those atoms that have nuclei identical in the number of protons, but different in the number of neutrons, are variants of one chemical substance and are called its isotopes. In order to somehow distinguish them to a symbol denoting an element, they attribute a number, which is the sum of all particles in the nucleus of this isotope. For example, the nucleus of the element uranium-238 includes 92 protons, as well as 146 neutrons, and uranium-235, also 92 protons, but neutrons are already 143. Most of the isotopes are unstable. For example, uranium-238, the bonds between protons and neutrons in the nucleus of which are very weak and sooner or later a compact group will be separated from it, consisting of a pair of neutrons and a pair of protons, turning uranium-238 into another element - thorium-234, also an unstable element, whose core contains 144 neutrons and 90 protons. Its decay will continue the chain of transformations, which will stop the formation of a lead atom. During each of these decays, energy is released that generates various types of radioactive radiation.
If you simplify the situation, you can describe the appearance of different types of radiation: alpha rays emit a nucleus, which consists of a pair of neutrons and a pair of protons, beta rays come from an electron. And there are situations in which the isotope is excited so that the particle’s output does not completely stabilize it, and then it dumps an excess of pure energy in one portion, this process is called gamma radiation. Such types of radiation as gamma rays, and the like x-rays, are formed without emitting material particles. The time required for the decay of half of all atoms of any particular isotope in any radioactive sources is called the half-life. The process of atomic transformations is continuous, and its activity is estimated by the number of decays that occur in one second and is measured in becquerels (1 atom per second).
Different types of radiation are characterized by the release of different amounts of energy, and their penetrating ability is also different, therefore, they also act differently on the tissues of living organisms.
Alpha radiation, which is a stream of heavy particles, can delay even a piece of paper, it is not able to penetrate through a layer of dead cells of the epidermis. It is not dangerous until substances that emit alpha particles penetrate the body through wounds or through food and / or inhaled air. Then they will become extremely dangerous.
Beta radiation is able to penetrate into the tissues of a living organism by 1-2 centimeters.
Gamma rays that travel at light speed are the most dangerous and can only be delayed by a thick slab of lead or concrete.
All types of radiation can cause damage to a living organism, and they will be the more, the more energy was transferred to the tissues.
In various accidents at nuclear facilities and during military operations with the use of nuclear weapons, it is important to consider the damaging factors affecting the body as a whole. In addition to the obvious physical effects on humans, various types of electromagnetic radiation are also harmful.