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Daughter nuclei

In this decay process, only one particle is emitted and, because energy is conserved, for each level in the daughter nucleus there is a unique a-particle energy. This means that a measurement of the differences in the energies of the a-particles emitted in a radioactive decay gives expHcidy the differences in the energies of the levels in the daughter nucleus. [Pg.448]

In this process only one particle is emitted, so the energy spectmm of the neutrinos consists of discrete lines and in principle the energies of the levels in the daughter nucleus could be deterrnined from this spectmm. However, the detection of neutrinos is very difficult, so this is not a practical possibihty. [Pg.449]

Fig. 4. Decay scheme ofas an example of /5 -decay, showing the spins and parities of the levels populated in the daughter nucleus and the energies in keV of these levels, where (" ) represents the principal decay mode, (—fc.) an alternative mode, and (- - ) is a highly improbable transition. Fig. 4. Decay scheme ofas an example of /5 -decay, showing the spins and parities of the levels populated in the daughter nucleus and the energies in keV of these levels, where (" ) represents the principal decay mode, (—fc.) an alternative mode, and (- - ) is a highly improbable transition.
Fig. 5. Decay scheme of showing the energies, spins, and parities of the levels populated in the daughter nucleus, Xe, and the energies in keV, emission probabihties (in %), and multipolarities of the y-ray transitions. There is a strong dependence of the y-ray lifetime on the y-character. The Ml + E2 y-ray of 177 keV has a half-hfe of 2.1 ps the half-hfe of the 164-keV M4 y-ray is 1.03 X 10 s. Fig. 5. Decay scheme of showing the energies, spins, and parities of the levels populated in the daughter nucleus, Xe, and the energies in keV, emission probabihties (in %), and multipolarities of the y-ray transitions. There is a strong dependence of the y-ray lifetime on the y-character. The Ml + E2 y-ray of 177 keV has a half-hfe of 2.1 ps the half-hfe of the 164-keV M4 y-ray is 1.03 X 10 s.
Nuclear reactions differ in some important ways from chemical reactions. First, different isotopes of the same element undergo essentially the same chemical reactions, but their nuclei undergo very different nuclear reactions. Second, when a or 3 particles are emitted from the nucleus, they leave behind a nucleus with a different number of protons. The product, which is called the daughter nucleus... [Pg.820]

The atomic number of the daughter nucleus is greater by l than that of the parent nucleus, because it has one more proton, but the mass number is unchanged, because the total number of nucleons in the nucleus is the same. [Pg.821]

The equation for the decay of a nucleus (parent nucleus - daughter nucleus + radiation) has exactly the same form as a unimolecular elementary reaction (Section 13.7), with an unstable nucleus taking the place of a reactant molecule. This type of decay is expected for a process that does not depend on any external factors but only on the instability of the nucleus. The rate of nuclear decay depends only on the identity of the isotope, not on its chemical form or temperature. [Pg.831]

The following nuclides lie outside the band of stability. Predict whether each is most likely to undergo p decay, P"1 decay, or a decay, and identify the daughter nucleus ... [Pg.843]

Write a nuclear equation for each of the following transformations (a) 25 Rf produced by the bombardment of califomium-245 with carbon-12 nuclei (b) the first synthesis of 266Mt by the bombardment of bismuth-209 with iron-58 nuclei. Given that the first decay of meitnerium is by a emission, what is the daughter nucleus ... [Pg.843]

The diagram above illustrates a nuclear reaction in which uranium-238 emits an alpha particle. How many protons and neutrons will the daughter nucleus have ... [Pg.7]

Gamma emission almost always follows some other decay process that results in an excited state in the daughter nucleus due to a nucleon being in a state above the ground state. [Pg.29]

In general, the daughter nucleus will have an initial abundance at time zero, which can be assumed to bear a constant ratio to another isotope of the same... [Pg.327]

Although many other types of nuclear reaction are possible as a result of high neutron fluxes, these two are the ones of prime importance in radioanalytical chemistry. The two principal requirements for a reaction to be useful analytically are that the element of interest must be capable of undergoing a nuclear reaction of some sort, and the product of that reaction (the daughter) must itself be radioactively unstable. Ideally, the daughter nucleus should have a half life which is in the range of a few days to a few months, and should emit a particle which has a characteristic energy, and is free from interference from other particles which may be produced by other elements within the sample. [Pg.53]

PGNAA involves the measurement of the prompt y rays emitted when the nuclei first absorb the neutrons. By energy and intensity analysis of the prompt y spectrum it is possible to reveal the elements present and determine their concentrations. Because the analysis is carried out during the irradiation, the method is quicker than delayed NAA, but it needs special equipment on site at the reactor to record the y spectrum whilst the sample is being irradiated (Glascock et al. 1984, Glascock 1994). It can, however, measure some elements more efficiently than delayed NAA (e.g., Pb), since it does not require the daughter nucleus to be radioactively unstable. [Pg.128]

The first four modes of radioactive decay can be plotted on a single diagram (Fig. 10.3), which allows for a prediction of the nature of the daughter nucleus from a parent subject to any one of the above processes. [Pg.236]

Meiosis A spedal method of cell division, occurring in maturation of the germ cells, by means of which each daughter nucleus receives half the number of chromosomes characteristic of the somatic cells of the species. [NIH]... [Pg.70]

Let us begin by considering the case when a radionuclide 1 decays with decay constant A.1 forming a daughter nucleus 2, which in turn decays with decay constant 2. Schematically, we have... [Pg.67]

Let us now consider a number of other special cases of Equations (3.21) and (3.22) that are of practical importance. Suppose the daughter nucleus is stable (k2 = 0). Then we have... [Pg.69]


See other pages where Daughter nuclei is mentioned: [Pg.448]    [Pg.448]    [Pg.448]    [Pg.448]    [Pg.821]    [Pg.947]    [Pg.823]    [Pg.340]    [Pg.352]    [Pg.379]    [Pg.379]    [Pg.1755]    [Pg.42]    [Pg.329]    [Pg.125]    [Pg.125]    [Pg.235]    [Pg.199]    [Pg.1801]    [Pg.274]    [Pg.274]    [Pg.61]    [Pg.8]    [Pg.170]    [Pg.178]    [Pg.178]    [Pg.179]    [Pg.181]    [Pg.181]   
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