What is gamma rays?

After the discovery of materials capable of spontaneous emission of elementary particles (radio emission as a result of decay), the study of their properties began. Active participation in the search for new and systematization of already existing knowledge in physics was made by the famous Curie couple, as well as E. Rutherford. He was the first to open gamma rays. The experiment he set was simple and, at the same time, brilliant.

Radium was taken as a source of radiation. A narrow hole was made in the thick-walled lead container. At the bottom of the resulting channel was placed radium. At a slight distance from the container perpendicular to the axis of the hole was a photosensitive element - a plate. In the interval between it and the container with radioactive material, a special installation could generate a high intensity magnetic field, the lines of tension of which were oriented parallel to the photosensitive plate. All elements except the field generator were in an airless environment to exclude the effect of air atoms on the result of the experiment. If Rutherford ignored this moment, gamma rays could be discovered by someone else.

In the absence of magnetic action, a dark spot appeared on the plate, indicating a rectilinear propagation of radiation (all other directions were simply cut off by the walls of the lead capacitance). But as soon as the magnetic field appeared, three spots appeared at once on the photosensitive element of the system. This meant that certain particles radiated by radium are deflected by the field. Rutherford suggested that the beam consists of at least three components. The nature of the deflection indicated that the particles of the two beams are electrically charged, and the third beam is electrically neutral. Moreover, the negative component of the initial radiation deviated much more pronouncedly than the positive one. The electrically neutral component is the gamma ray. A component with a negative charge is called beta-rays, and the last, positive charge is alpha-ray.

In addition, they behaved differently in a magnetic field, the rays had different properties. Gamma rays are able to penetrate into matter for quite a long distance. Thus, a lead plate 1 cm thick reduces their intensity only by a factor of two. The alpha beam can be stopped even by a thin sheet of paper. But the beta radiation takes an intermediate position: stop the flow can be a metal a few millimeters thick.

Subsequently it became clear that:

• Beta-ray is a stream of negatively charged particles (electrons) moving at high speed;
• Alpha-ray are helium nuclei, very stable formation;
• Gamma ray - one of the varieties of electromagnetic waves. The emission spectrum is completely linear, since the emitting core is characterized by discrete energy states. Represent in the form of levels of energy distribution of the emitted quanta. The term "gamma radiation" is increasingly being used not only to describe the processes of radioactive decay, but, in general, for any hard radiation of an electromagnetic nature in which each quantum corresponds to an energy of not less than 10 keV. The source of this type of radiation are electrons in the structure of excited atoms. Excess energy transfers electrons to higher energy levels. From there they return to the previous state, allocating radiation in the form of X-rays or light (electromagnetic waves). The spectrum of electromagnetic radiation in the case of gamma rays is extremely small and is no more than 5 * 0.001 nm because of which the properties of particles, rather than waves, are more clearly manifested.