This quick reference has been prepared as a resource for field personnel, e.g., for those in the area of Homeland Security.

Table I is based on the author’s Nuclear Wallet Cards, last produced in January 2000 and updated using data given in Evaluated Nuclear Structure Data File [1]. The data for Table II are taken from reference [1].

Explanation of Table I

All naturally-occurring radioactive nuclides and others with half-life (T_1/2)≥1 h and Z≤100 are included. The shorter T_1/2 given are those seen as decay products of long-lived radioactive chains occurring in nature.

Nuclide: Nuclides are listed in order of increasing atomic number (Z), and are subordered by increasing mass number (A).

Long-lived excited states are denoted by the symbol "m" after the mass number. Radionuclides which occur in nature [2] and some of the other well known radioactive nuclides appear with bold A-number.

Half-Life, T_1/2 is given followed by its units (s: second, m: minute, h: hour, d: day, y: year).

Major Radiations: Only α, ε, β^-, γ, and SF (spontaneous fission) are indicated. Electron capture without significant X-/γ-ray emissions are given as ε.

Major Gamma Radiation energies in decay, of the parent nuclide are given. The maximum of three X/γ rays, with intensity > 2 %, are given. The 2^nd transition is omitted if it is <1 % of first transition. The third transition is omitted if it is <10 % of the 2^nd transition. The X/γ rays given belong to the daughter nuclide alone. In case of the daughter nuclide being radioactive one could observe X/γ rays from several nuclides down the decay chain. A ²³⁵U source, for example, in equilibrium with its daughters (as it occurs in nature) will show activity from several nuclides in the decay chain.

Explanation of Table II

Table II lists the X-/γ-ray energies with their parent associations. The X-/γ-ray energies > 100 keV and < 3000 keV are listed. Only those nuclides for which X-/γ-ray intensities are >5 % are included. Only immediate parents are included.

Acknowledgements

The author is grateful for encoragement and support from P. Bond and P. Oblozinsky, Brookhaven National Laboratory. Helpful comments from J. Morgan, Lawrence Livermore National Laboratory, and many colleagues in the area of homeland security were appreciated.

The research was supported by the Office of Nuclear Physics, Office of Science, U.S. Department of Energy.

References

1. Evaluated Nuclear Structure Data File- Maintained by the National Nuclear Data Center, Brookhaven National Laboratory.
2. Chart of Nuclides 16^th Edition, 2002. Knolls Atomic Power Laboratory, Lockheed Martin Corporation.