belbear wrote:
From an engineering point of view, a spherical device will be extremely difficult to construct because you can’t start from a stack of flat foils.
Most practical will be a cylinder with a flat endcap (and a hole to let the alpha beam pass through). The vacuum vessel will probably already have this shape.
a cylinder of foil would be rather easy to build, yes. but spherical shapes could be made with something like ion beam spattering, alternating layers having different opacity to xrays, and different electrical conductivity.
