physical law of radioactive decay was formulated after the 1896 Becquerel discovered the phenomenon of radioactivity.It is an unpredictable transition of some types of nuclei in the other, and they emit different types of radiation and particle elements.The process happens naturally when seen from the naturally occurring isotopes and artificial, in the case of obtaining these in nuclear reactions.That core which breaks up, it is considered the mother, but it turned out - a subsidiary.In other words, the fundamental law of radioactive decay involves an arbitrary natural process of transformation of one nucleus to another.
study Becquerel showed the presence of uranium salts previously unknown radiation that affects the photographic plate, fill the air with ions and had the property to pass through thin plates of metal.Experiments M. Pierre Curie and radium and polonium confirmed the withdrawal, as described above, and in science, a new concept, called the doctrine of radiation.
This theory, which reflects the law of radioactive decay, is based on the assumption of a spontaneous process, which is subject to statistics.Since individual nuclei decay independently of each other, it is considered that the average number of decayed over time in proportion nondecomposed by the end of the process.If you follow an exponential law, the number of recent decreases significantly.
intensity of the phenomenon is characterized by two main properties of radiation: the period of the so-called half-life and life span sredneraschitanny radioactive nucleus.The first is between millionths of a second to billions of years.Scientists believe that these nuclei do not grow old, and for them there is no concept of age.
Law of radioactive decay is based on the so-called rules of the displacement, and they, in turn, are a consequence of the theory of preserving the core of the charge and of the mass.It was established experimentally that the effect of the magnetic field acts in different ways: a) the bending of light rays occurs as a positively charged particles;b) as a negative;c) do not show any reaction.This implies that the radiation is of three types.
The same species there are and the process of decay: with the release of an electron;positron;the absorption of one electron core.Proved that the kernel corresponding to their lead structure, experienced decay with the emission.The theory became known as alpha decay and has been formulated GA Gamow in 1928.The second version was formulated in 1931 by Enrico Fermi.His research showed that instead of electrons, some types of nuclei emit particles opposite - positrons, and it is always accompanied by the emission of a particle with zero electric charge and rest mass neurine.The simplest example of beta decay is considered a neuron in proton transfer with a time period of 12 minutes.
These theories, considering the laws of radioactive decay, were the main before 1940 19th century until the Soviet physicists GN Flerov and KA Petrzhak not opened another kind, in which the nucleus of uranium spontaneously divided into two equal particles.In 1960 he was predicted double-proton radioactivity and-neutron.But up to now this type of decay is not confirmed experimentally received and has not been found.It was open only proton radiation at which the emission of a proton from the nucleus.
deal with all these issues is difficult, although the law of radioactive decay is simple.It is not easy to understand its physical meaning and, of course, the presentation of this theory goes far beyond the program of physics as a subject in school.
