Plutonium radiation surrogate
View Patent ↗A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little α-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.
1. A radiation surrogate for weapons-grade plutonium, comprising in combination the radioisotopes: Ba-133 having an activity of between 5 and 5.5 μCi, Cf-252 having an activity of between about 4 and about 5 μCi, Cs-137 having an activity of between about 10.2 and about 10.4 μCi, Gd-153 having an activity of between about 350 and about 550 μCi, Lu-177m having an activity between about 40 and about 50 μCi, Sn-113 having an activity between about 13.5 and about 30 μCi, and Zr-95 having an activity between about 1 and about 6 μCi; wherein said combination of radioisotopes is substantially surrounded by tungsten foil.
2. The radiation surrogate of claim 1 , wherein said radioisotopes in said combination of radioisotopes are individually sealed.
3. The radiation surrogate of claim 2 , wherein said individually sealed radioisotopes in said combination of radioisotopes are disk-shaped.
4. The radiation surrogate of claim 3 , further comprising a cylindrical polycarbonate holder for holding said disk-shaped radioisotopes in said combination of radioisotopes in a stacked configuration.
5. The radiation surrogate of claim 4 wherein said combination of radioisotopes is disclosed in a thermoset resin container.
6. The radiation surrogate of claim 5 , wherein said resin container is a clear plastic container.
7. The radiation surrogate of claim 6 , wherein said resin container is a spherical container.
8. The radiation surrogate of claim 1 , wherein said combination of radioisotopes further comprises at least one radioisotope selected from the group consisting of Co-57 having an activity of about 33 μCi, and Th-228 having an activity of about 4 μCi.
9. The radiation surrogate of claim 8 , wherein said combination of radioisotopes is substantially surrounded by tungsten foil.
10. The radiation surrogate of claim 8 , wherein said radioisotopes in said combination of radioisotopes are individually sealed.
11. The radiation surrogate of claim 10 , wherein said individually sealed radioisotopes in said combination of radioisotopes are disk-shaped.
12. The radiation surrogate of claim 11 , further comprising a cylindrical polycarbonate holder for holding said disk-shaped radioisotopes in said combination of radioisotopes in a stacked configuration.
13. The radiation surrogate of claim 11 wherein said combination of radioisotopes is disposed in a thermoset resin container.
14. The radiation surrogate of claim 13 , wherein said resin container is a clear plastic container.
15. The radiation surrogate of claim 14 , wherein said resin container is a spherical container.