Electromagnetic radiation y-ray

Compton effect. One of the principal processes by which high-energy electromagnetic radiation (y-rays) interacts with or is absorbed by matter. In the Compton process the y-ray frees an electron in matter as if the electron were unbound, dividing the momentum of the y-ray between the ejected electron and a new y-ray of lower energy going off in a new direction. 

Radioactivity is a phenomenon in which small particles of matter (a or (3 particles) and/or electromagnetic radiation (y rays) are emitt by imstable atomic nuclei. 

The nucleus would thus seem to consist of independrat substructures of neutrons and protons, with each type of nucleon paired off as far as possible. Further, the nucleons obviously grouped together in the magic numbers. From the decay of radioactive nuclei we know that the total decay energy (Q-value) of any particular nuclide has a definite value. Moreover, y-emission from any particular nucleus involves discrete, definite values. These facts resemble the quantized emission of electromagnetic radiation (X-ray, UV, visible light. 

High energy radiation is defined as all forms of radiation with energies much higher than those of chemical bonds. It includes both electromagnetic radiation (x-rays, y-rays, etc) and particulate beams (a- and 8-particles, electrons. 

Spectroscopy is basically an experimental subject and is concerned with the absorption, emission or scattering of electromagnetic radiation by atoms or molecules. As we shall see in Chapter 3, electromagnetic radiation covers a wide wavelength range, from radio waves to y-rays, and the atoms or molecules may be in the gas, liquid or solid phase or, of great importance in surface chemistry, adsorbed on a solid surface. 

Gamma rays (y rays), which are high-energy, short wavelength, electromagnetic radiation particles that originate from within the nucleus... 

Arrange the following types of photons of electromagnetic radiation in order of increasing energy -y-rays, visible light, ultraviolet radiation, microwaves, x-rays. 

One of the first proposed processes for obtaining electromagnetic radiation up to the X/y-ray range using laser beams was the Thomson scattering (see e.g., [88] and references therein). As it is known, this is the scattering of... 

For many of the analytical techniques discussed below, it is necessary to have a source of X-rays. There are three ways in which X-rays can be produced in an X-ray tube, by using a radioactive source, or by the use of synchrotron radiation (see Section 12.6). Radioactive sources consist of a radioactive element or compound which spontaneously produces X-rays of fixed energy, depending on the decay process characteristic of the radioactive material (see Section 10.3). Nuclear processes such as electron capture can result in X-ray (or y ray) emission. Thus many radioactive isotopes produce electromagnetic radiation in the X-ray region of the spectrum, for example 3He, 241Am, and 57Co. These sources tend to produce pure X-ray spectra (without the continuous radiation), but are of low intensity. They can be used as a source in portable X-ray devices, but can be hazardous to handle because they cannot be switched off. In contrast, synchrotron radiation provides an... 

Excitation by X Rays. As forms of electromagnetic radiation, X and y rays follow the same absorption rules as photons. Because of the high energy of the secondary... 

A few radioisotopes of biochemical significance are y emitters. Emission of a y ray (a photon of electromagnetic radiation) is often a secondary process occurring after the initial decay by /3 emission. The disintegration of the isotope 131I is an example of this multistep process. 

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