Re: Meanwhile, back in the lab...

Greg, was my last question to you too difficult to answer off hand?

The question I have is this: what happens when you run "few mev"
protons or neutrons through single crystals of (say) graphite at small
angles in comparison to the plane defined by the sheets of C atoms.
With the beam passing orthogonally (the 001 direction) through the
common plane defined by the stacked sheets, you'd get one attenuation
coeefficient. And presumably at right angles to that, so the particles
were passing straight down the "alleys" between the sheets (the 112
direction) you'd get another coefficient. In both cases these would
related to the average density of the crystal in the direction of
interest. But now, what happens when you tilt the thing just a little
in either direction from 112??? Do the particles now go off greatly to
one side or the other? And is the effective shielding coefficient per
mass a LOT greater in the direction where the particles DON'T go, than
you could get with other materials?

.