In a fusion, or H Bomb, the tritium (which is just hydrogen with an extra two neutrons) is that which produces the boom -- the main fuel, as it were. Its a "neutron source" only in the weakest possible sense -- the same way dynamite might be considered to need nitroglycerine as a "neutron source". (I'm not sure that people outside of the bomb building industry really know *for sure* what the geometries used in the atomic weapon that sets off the fusion reaction.)
I don't understand your point. The earliest devices used a pie shape with a wedge cut out. The actual geometry is rather unimportant to getting a fission reaction - but it *is* important if you want to maximize your yield. -- Ed Carp, N7EKG Ed.Carp@linux.org, ecarp@netcom.com Finger ecarp@netcom.com for PGP 2.5 public key an88744@anon.penet.fi If you want magic, let go of your armor. Magic is so much stronger than steel! -- Richard Bach, "The Bridge Across Forever"