Defense Intelligence Reference Document Aneutronic Fusion Propulsion(1)

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13T + 13T ➔ 2 x 0 1n + 24He + [11.3 MeV split between the neutrons and helium]
Figure 7. Low Temperature Fusion Reactions.
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• [>QO ,, - -D-1
,, -cc,, - • D-He3
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1 E-0, I ,
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I I
1 E-04 I
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Deuteron Enersv(keV)
Figure 8. Fusion Ignition Energies for D-T, D-D, and D-He3.
Figure 8 shows the probabilities of these reactions occurring, expressed in units of
barns (1 b = 10-28 m2). The D-T reaction becomes increasingly probable as the energy
of the deuterium nucleus (deuteron) reaches about 5 keV. In terms of temperature,
this equals about 10 million degrees kelvin. At 10 keV (100 million degrees kelvin), the
two D-D reactions listed in Figure 7 become more probable and D-He3 fusion becomes
viable at 30 keV (300 million degrees kelvin). There are several ways to achieve these
temperatures in a controlled manner. For example, Edward Teller and Stanislaw Ulam
developed a design for a fusion, or thermonuclear bomb, that used a plutonium fission
atomic bomb to reach the ignition temperature for fusion. Deuterium is the most useful
fuel for low-temperature fusion reactors, and there is a limitless supply available by
centrifuging ordinary tap water to separate out heavy water (D2O).
Because of deuterium's availability, a strong incentive exists to develop manageable
ways to initiate nuclear fusion, concentrating on the fusion schemes outlined in Figure 6;
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