Defense Intelligence Reference Document Advanced Nuclear Propulsion For Manned Deep Space Missions

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= 100 petawatts, certainly powerful enough to compress the deuterium to more than
thousandfold density.
With the entrapment of the neutrons comes an increase of the specific impulse. With 38
percent of the energy going into the kinetic energy of the neutrons and 62 percent into
charged fusion products, the specific impulse is increased by the factor
.Jt +38/62 = .J!0/6.2 = 1.275. This increases the maximum exhaust velocity from
v =1.Sx 109 cm/s to v =l.9x 109 cm/s = 0.063c.
In the course of the thermalization in the supercompressed plasma, the neutron
absorption cross section is greatly increased, both in the liner and tamp, with the liner
also compressed to high densities. If the liner and tamp are made from boron, which
has a large neutron-absorption cross section, the spacecraft is heated only by a greatly
reduced thermal neutron flux, and only this much smaller amount of heat must be
removed by a radiator.
Testing the Deuterium Microdetonation Concept
For the Orion bomb propulsion concept, testing was a serious problem. If tested on the
Earth, it would have resulted in the large fallout of fission products. These tests would
have been needed to study the survival of the pusher plate under the repeated
exposure of kiloton fission explosions (or fusion-boosted explosions). Of course, the
tests could have been carried out in space, but this would have been extremely
expensive, because it would have required launch by chemical rockets of the huge
Orion spaceship into space. Fortunately, this is not necessary for the deuterium
microdetonation propulsion concept because there exists an alternative way to generate
a 107-ampere GeV proton beam: replacing the huge spaceship used as a large capacitor
to be charged up to gigavolt potentials with a "Super Marx generator" (Reference 16).
This Super Marx generator can achieve on Earth what the huge spaceship can achieve
in space: the generation of gigavolt 10 7-ampere proton beams. Since the realization of
pure deuterium beams would obviously be a breakthrough in fusion, the expenditure for
the development of a Super Marx generator would be well justified.
Up until now nuclear fusion by inertial confinement has been achieved only using large
fission explosives as a means (driver) for ignition. From this experience we know that
the ignition is easy with sufficiently large driver energies, difficult to duplicate with
lasers or electric pulse power by an ordinary Marx generator. The problem therefore is
not the configuration of the thermonuclear explosive but the driver, be it for the ignition
of pure deuterium (D) as in the Mike Test or for the ignition of deuterium-tritium (DT)
as in the Centurion-Halite experiment, because for sufficiently large driver energies the
target configuration is of secondary importance.
Substantially larger driver energies can be reached with the "Super Marx generator." It
can be viewed as a two-stage Marx generator, where a bank of ordinary Marx
generators assumes the role of a first stage. If the goal is the much more difficult
ignition of a pure deuterium microexplosion, the Super Marx generator must in addition
deliver a much larger amount of energy (compared with that of the most powerful
lasers) and also generate a magnetic field in the thermonuclear target that is strong
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