----- Original Message -----
From: "Michael Foster"
I have the D2; I usually
have liquid nitrogen on hand, but is neutron detection
difficult or expensive?
It is relatively easy with CR-39 film. See Prof.L. Kowalski's
site:
http://blake.montclair.edu/~kowalskil/cf/185about39.html
Avoid the expensive neutron-only He3 detectors unless you are
well-heeled and can afford the very best, as the cheaper ones are
not accurate. If anything, Mizuno's measurements were on the low
side (if he missed the very low energy neutron spectrum). There
could have been more than he takes credit for.
This film method is both easy, accurate and fairly cheap. It
cannot be fooled by RF as can GM or other high voltage tubes.
There is some evidence that neutrons from "stripping" can be very
low in kinetic energy - subthermal even - in which case they do
not get picked up with as good accuracy with just CR-39 (maybe)
but a setup with two detectors CR-39 plus a borax covered GM tube
might help. There are some good tips for high kinetic neutron
detection on the Farnsworth site.
Jones
