Preliminary Remediation Goals for Radionuclides (PRG)
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Decay Chain
Using the Radionuclide Decay Chain Tool
1. Select Isotope
2. Decay Chain Table
3. Decay Chain Animation
| 1. Select Isotope
Select the isotope of interest and click the "Submit" button.
2. Decay Chain Table
A table of the ICRP 107 decay
chain appears that displays the parent and all daughters in the decay
chain through the stable isotope(s). The half-life, decay modes, and the
branching fractions are given. Decay chains that are repeated as a
result of multiple branching fractions are only presented once in the
table. Text below the decay chain table contains decay mode definitions and further information on the daughters
included in the +D slope factors for risk assessment purposes. A back
button is provided to return to the main page. To watch an animated
representation of the decay process, click the link "Click for animated diagram of the decay chain."
3. Decay Chain Animation
The parent isotope
and the daughters are slowly drawn. Inside the representative atoms, the
atomic mass and half-life are given for the isotope. The decay mode and
the branching fraction are displayed beside the decay arrows. Stable
isotopes are presented in green. Click here to see an
example. When a decay is by spontaneous fission,
the resulting representative atom is shown in white with SF displayed in
the center. Hover the cursor over an isotope to increase the size. Decay
chains that are repeated as a result of multiple branching fractions are
only presented once in the drawing to retain a manageable size. A chain
that does not end in a green stable isotope is presented elsewhere in
the drawing. While the chain is being drawn, atoms will briefly flash to
signify where an incomplete chain is continued. Also, if the user hovers
the cursor over the last atom in an incomplete chain, the atom that
continues the chain will increase its size. The animation speed can be controlled and a button is
provided to restart the drawing if desired. When the decay requires more
space than the drawing window, scrollbars will appear. A back button is
provided to return the user to the previous page.
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