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The thorium-234 produced above experiences two successive beta decays: Gamma rays have very great penetrating power and are not affected at all by a magnetic field.They move at the speed of light and have a very short wavelength (or high frequency); thus they are a type of electromagnetic radiation (see gamma radiationgamma radiation,high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity.actinide series,a series of radioactive metallic elements in Group 3 of the periodic table.Members of the series are often called actinides, although actinium (at. 89) is not always considered a member of the series......neutrino[Ital.,=little neutral (particle)], elementary particle with no electric charge and a very small mass emitted during the decay of certain other particles.The neutrino was first postulated in 1930 by Wolfgang Pauli in order to maintain the law of conservation of energy..... The electron is immediately ejected from the nucleus, and the net result is an increase of 1 in the atomic number of the nucleus but no change in the mass number.Other, less common, types of radioactivity are electron capture (capture of one of the orbiting atomic electrons by the unstable nucleus) and positron emission—both forms of beta decay and both resulting in the change of a proton to a neutron within the nucleus—an internal conversion, in which an excited nucleus transfers energy directly to one of the atom's orbiting electrons and ejects it from the atom.
The biological action of radiation is not fully understood, but it is believed that a disturbance in cellular activity results from the chemical changes caused by ionization (see.....
The lifetime of a radioactive substance is not affected in any way by any physical or chemical conditions to which the substance may be subjected.
The rate of disintegration of a radioactive substance is commonly designated by its half-lifehalf-life,measure of the average lifetime of a radioactive substance (see radioactivity) or an unstable subatomic particle.
Alpha rays are nuclei of ordinary helium atoms (see alpha particlealpha particle,one of the three types of radiation resulting from natural radioactivity.
Alpha radiation (or alpha rays) was distinguished and named by E. Rutherford in 1909, who found by measuring the charge and mass of alpha particles that they are the nuclei of ordinary..... Alpha decay reduces the atomic weight, or mass number, of a nucleus, while beta and gamma decay leave the mass number unchanged.
particle accelerator,apparatus used in nuclear physics to produce beams of energetic charged particles and to direct them against various targets.