Gamma radiation emission

Emission of alpha and gamma radiation Emission of beta radiation Decay chain... 

Alpha particle emission Beta particle emission Gamma radiation emission... 

The origin of the rays was initially a mystery, because the existence of the atomic nucleus was unknown at the time. However, in 1898, Ernest Rutherford took the first step to discover their origin when he identified three different types of radioactivity by observing the effect of electric fields on radioactive emissions (Fig. 17.4). Rutherford called the three types a (alpha), (3 (beta), and y (gamma) radiation. 

The Mossbauer effect, discovered by Rudolf L. Mossbauer in 1957, can in short be described as the recoil-free emission and resonant absorption of gamma radiation by nuclei. In the case of iron, the source consists of Co, which decays with a half-life of 270 days to an excited state of Fe (natural abundance in iron 2%). The latter, in turn, decays rapidly to the first excited state of this isotope. The final decay generates a 14.4 keV photon and a very narrow natural linewidth of the order of nano eV. 

Counter, Scintillation—The combination of phosphor, photomultiplier tube, and associated circuits for counting light emissions produced in the phosphors by ionizing radiation. Scintillation counters generally are more sensitive than GM counters for gamma radiation. 

Some radioisotopes decay emitting only gamma rays, but many do so by the concurrent emission of beta and gamma radiation. The rate at which radiation is emitted from the nuclei of different radioisotopes varies considerably. Each radioisotope has a unique form of decay that is characterized by its half-life (tV2), the time it takes for the radioactivity of the radioisotope to decrease by one-half of its original value (see Textbox 14). 

Gamma radiation is the emission of very shortwave electromagnetic radiation. 

Gamma counters are a type of ectrttillatlfri counter add measure gamma radiation by detectlngthe emission of light Induced in a scintiBsnt... 

The Mossbauer effect involves the resonance fluorescence of nuclear gamma radiation and can be observed during recoilless emission and absorption of radiation in solids. It can be exploited as a spectroscopic method by observing chemically dependent hyperfine interactions. The recent determination of the nuclear radius term in the isomer shift equation for shows that the isomer shift becomes more positive with increasing s electron density at the nucleus. Detailed studies of the temperature dependence of the recoil-free fraction in and labeled Sn/ show that the characteristic Mossbauer temperatures Om, are different for the two atoms. These results are typical of the kind of chemical information which can be obtained from Mossbauer spectra. 

The nuclear reaction in the hydrogen bomb that produced fermium was the result of the acquisition of 17 neutrons by uranium from the explosion resulting in uranium-255 and some gamma radiation. U-255 decays by (3-electron emission to form fermium-255, as depicted in the equation as follows ... 

Gamma Radiation. The combined process of emission, transmission and absorption of gamma rays, as from, the expln of atomic bomb Ref Glossary of Ordn (1959), 133 L... 

Any hydrogenated candidate for the unknown IR emission must exhibit sufficient stability to the harsh conditions of the interstellar medium, including bombardment by particles and ultraviolet and gamma radiation. Equally important, for a species to be considered a viable candidate, its spectra must reproduce two important characteristics found in most diffuse medium spectra. These are (a) that the 1,300 cm-1 band be more intense than the 880 cm-1 band (Williams 1996), and (b) that the spacing between it and the next main emission feature match the canonical interstellar spacing of 300 cm-1 (Hudgins and Allamandola 1999). 

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