if uranium-238 undergoes alpha decay the daughter nucleus will be fission products.
if uranium-238 undergoes alpha decay the daughter nucleus will be fission products.
if uranium-238 undergoes alpha decay the daughter nucleus will be?
fission products
Na
Na
the shell closure at "n" = 184 is predicted to result in longer partial half-lives for alpha decay and spontaneous fission. it is believed that the shell closure will result in higher fission barriers for nuclei around fl, strongly hindering fission and perhaps resulting in fission half-lives 30 orders of magnitude greater than those of nuclei unaffected by the shell closure. for example, the doubly magic nucleus fl may have a spontaneous fission half-life on the order of 10 years; this is much longer than the 2.5 ms half-life of the known neutron-deficient isotope fl (with "n" = 170) believed to demarcate the limit of stabilizing effects. some undiscovered isotopes are predicted to undergo fission with still shorter half-lives, limiting the existence and possible observation of superheavy nuclei beyond the island of stability (namely for "z"  120 and "n"  184; these nuclei may undergo alpha decay or spontaneous fission in microseconds or less). in the center of the island, there may be competition between alpha decay and spontaneous fission, though the exact ratio is strongly model dependent. the alpha-decay half-lives of 1700 nuclei with 100 ≤ z ≤ 130 have been calculated in a quantum tunneling model with both experimental and theoretical alpha-decay q-values, and are in agreement with observed half-lives for some of the heaviest isotopes. the longest lived isotopes are predicted to lie on the beta-stability line as well, for beta decay is predicted to compete with the other decay modes near the predicted center of the island, especially for isotopes of elements 111–115. the possible role of beta decay is highly uncertain, as isotopes of these elements (such as fl and mc) are predicted to have shorter partial half-lives for alpha decay; this would reduce competition and result in alpha decay remaining the dominant decay channel, unless additional stability towards alpha decay exists in superdeformed isomers of these nuclides. considering all decay modes, various models indicate a shift of the center of the island (i.e. the longest-living nuclide) from fl to a lower atomic number; these include 100-year half-lives for cn and cn, a 1000-year half-life for cn, and a 300-year half-life for ds; the latter two exactly at the "n" = 184 shell closure.
island of stability