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The valley of stability can be helpful in interpreting and understanding properties of nuclear decay processes such as decay chains and nuclear fission. The uranium-238 series is a series of α (N and Z less 2) and β− decays (N less 1, Z plus 1) to nuclides that are successively deeper into the valley of stability.
In nuclear physics, the island of stability is a predicted set of isotopes of superheavy elements that may have considerably longer half-lives than known isotopes of these elements. It is predicted to appear as an "island" in the chart of nuclides , separated from known stable and long-lived primordial radionuclides .
All "stable" isotopes (stable by observation, not theory) are the ground states of nuclei, except for tantalum-180m, which is a nuclear isomer or excited state. The ground state, tantalum-180, is radioactive with half-life 8 hours; in contrast, the decay of the nuclear isomer is extremely strongly forbidden by spin-parity selection rules.
Islands of stability are predicted to center near 294 Ds and 354 126, beyond which the model appears to deviate from several rules of the semi-empirical mass formula. [ 8 ] The general patterns of beta-stability are expected to continue into the region of superheavy elements , though the exact location of the center of the valley of stability ...
An even number of protons or neutrons is more stable (higher binding energy) because of pairing effects, so even–even nuclides are much more stable than odd–odd. One effect is that there are few stable odd–odd nuclides: in fact only five are stable, with another four having half-lives longer than a billion years.
The liquid drop model is one of the first models of nuclear structure, proposed by Carl Friedrich von Weizsäcker in 1935. [5] It describes the nucleus as a semiclassical fluid made up of neutrons and protons, with an internal repulsive electrostatic force proportional to the number of protons.
With 57 nuclear reactors, France produces more than two-thirds of its electricity from nuclear power. Last year, it exported a record amount, about 17% of its production, mostly to Italy.
Nuclear stability is limited to those combinations of protons and neutrons described by the chart of the nuclides, also called the valley of stability.The boundaries of this valley are the neutron drip line on the neutron-rich side, and the proton drip line on the proton-rich side. [2]