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Earth and Space Sciences · 术语表

什么是 Short-lived radionuclide？

Definition 2.12 University Earth and Space Sciences — Year 2 · 第 2 章 — Planet Formation and Meteorites

A short-lived radionuclide is a radioactive nuclide with a half-life of roughly $0.1$ to $100\,\mathrm{Myr}$ , present when the Solar System formed and now extinct, whose former presence is shown by an excess of its daughter in minerals that were rich in its element.

nuclide	daughter	reference	half-life (Myr)	early ratio
$\ce{^{26}Al}$	$\ce{^{26}Mg}$	$\ce{^{27}Al}$	0.717	$5.23\times10^{-5}$
$\ce{^{60}Fe}$	$\ce{^{60}Ni}$	$\ce{^{56}Fe}$	2.62	$1.0\times10^{-8}$
$\ce{^{53}Mn}$	$\ce{^{53}Cr}$	$\ce{^{55}Mn}$	3.74	$7\times10^{-6}$
$\ce{^{107}Pd}$	$\ce{^{107}Ag}$	$\ce{^{108}Pd}$	6.5	$6.6\times10^{-5}$
$\ce{^{182}Hf}$	$\ce{^{182}W}$	$\ce{^{180}Hf}$	8.90	$1.02\times10^{-4}$
$\ce{^{129}I}$	$\ce{^{129}Xe}$	$\ce{^{127}I}$	15.7	$1.28\times10^{-4}$

Table 2.3. Some short-lived radionuclides of the early Solar System, their stable daughter, the stable isotope of the same element used as reference, their half-life and their ratio to the reference when the CAIs formed. Data: Lugaro and others (2018).

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