Death-Rays as Life-Savers in the Third Reich - Pedro Waloschek ...

atl much lower electron energies, where the produced X-rays are
distributed more or less evenly in all directions, across the entire
space. The more energy there is, the narrower becomes the cone in
which the X-rays are produced. This kind of intense bundling is of
major importance when the aim is to direct the produced radiationto a
target.
Another important aspect is the range of the radiation when it
penetrates matter. I shall go into this subject in more detail later on.
This concerns on one side the range in air, i.e. ensuring that sufficient
radiation reaches its target, but on the other side the radiation should
also be able to penetrate relatively thick walls or shields made from
solid materials. In both cases the calculations are the same in principle.
Based on density it is possible to predict that the range in solid
materials will be roughly a factor thousand smaller than in gasses under
atmospheric pressure, which includes air. In the latter case it is
necessary to calculate the distance at which a device may still be able
to irradiate an object with sufficient intensity to cause some defined
damage or, in extreme cases, the death of the irradiated human being.
Naturally, this was what the military were hoping to achieve. By then
medicine had already provided some data on the radiation dose
required to damage or kill cells (such as cancer cells) or an entire living
creature. Schmellenmeier assumed that he would never be able to
achieve such a high level of intensity.
The penetration of solid materials is interesting for quite different
reasons. It was already known that ‘harder’ X-rays, i.e. produced by
electrons of higher energy, could penetrate thicker layers of matter.
Materials research experts could only dream of 20 to 100 MeV Xrays
that would enable them to X-ray thick work pieces. But that kind
of Voltage (to which the electrons would first have to be accelerated)
was not available in those days.
Relatively little was known at the time about the range in air of
high-energy X-rays. To meet military requirements the range needed
to be at least one, although preferably several kilometres in order to
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