Beta Decay

Beta Decay

The Beta Decay with suitable examples and sketches are discuss here advanced. Beta Decay is needed to read as engineer student.

What is radiation emitted by radioactive nuclei? Almost immediately, scientists found that this radiation is heterogeneous in composition. In 1899, the prominent French physicist Henri Becquerel and a number of other scientists showed that under the influence of a magnet part of the radiation deviates, while the other propagates in a straight line

 experiment on radiation deflection
experiment on radiation deflection

Diagram of the experiment on radiation deflection, where K is a lead container, P is a radioactive preparation, F is a photographic plate, and B is a magnetic field.

In addition, it was found that rays deflecting in a magnetic field are divided into two streams in an electric field, i.e. are positively and negatively charged particles. The English physicist Ernest Rutherford called the first type of radiation “alpha-rays”, and the second “beta-rays.” Radiation not deviating in a magnetic field was soon called “gamma rays.” A little later it turned out that gamma rays are similar to ordinary light, but their energy is much greater than the energy of light radiation. In 1900, Rutherford established that beta rays are simply a stream of electrons (e–); in 1906, he also showed that alpha rays are a stream of helium nuclei (42He) without electron shells.

In 1902-1907, the existence of radioactive series was discovered, i.e. sequences of natural radioactive isotopes: each subsequent isotope is formed from the previous one by decay with the emission of an alpha or beta particle. Consider the types of radioactive decay. The affiliation of radioactive decay to one form or another is related to the type of emitted particles. Alpha decay is possible for heavy nuclei with a sufficiently large charge Z> 60 (i.e., after neodymium Nd). In α decay, one element turns into another with a charge less by 2; in this case, the mass number of the nucleus decreases by 4. During the transformation, an α-particle (4He nucleus) flies out of the nucleus, which before decay was part of the nucleus.

β decay – radioactivity types

n → p + β – + ν, or simplified n → p + β – + ν Antineutrinos, as well as neutrinos, are particles open at the tip of a pen. When studying beta decay, it turned out that the law of conservation of energy is not satisfied; judging by the spectra of beta particles, part of it simply disappeared into nowhere. The question was so acute that in 1931 the famous Danish physicist Niels Bohr at the Rome Conference came up with the idea of ​​non-conservation of energy! However, there was another explanation – some unknown and invisible particle carries away the lost energy.

In 1933, at the Solvay Congress in Brussels, the famous physicist Wolfgang Pauli proposed the existence of a certain particle that practically does not interact with matter – neutrinos. This particle was discovered in 1953 by American scientists Raines and Cohen. The neutrino interacts so weakly with matter that it is able to freely penetrate the thickness of the Earth. In the formulas given in this manual, the entry means that the particle has a zero charge and mass number 1 (this is a neutron), – the particle has a charge 1 and mass number 1 (proton), etc. Please note that in the case of beta decay, the sum of mass and charge numbers is preserved.

β –– decay radioactivity types
β –– decay

The conversion of neutrons into protons can occur in a free state, for example, when neutrons fly toward us from the Sun, where they are obtained as a result of thermonuclear reactions. If the decay takes place in the nucleus, then the nucleus, as it were, loses one neutron and acquires one proton. As a result, the charge increases by 1, and the mass does not change. Here is an example:

Cs → Ba + β – + ν, or simply 137Cs → 137Ba + β – + ν And since the charge of the nucleus means that it belongs to one or another element, it turns out that in the process of radioactive decay, one element transforms into another – in this example, cesium Cs is converted to barium Ba. In nuclei with a lack of neutrons (although this is a rarer case), the conversion of a proton into a neutron can take place.

The Beta Decay with suitable examples and sketches are discuss here advanced. Beta Decay is needed to read as engineer student.

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