starship-design: antimatter--designs

[bfranchuk <bfranchuk@jetnet.ab.ca>]

KellySt@aol.com wrote:
> 
> > Why do you doubt the 20,000 pound figure for the pion
> > engine?  The pion engine could simply be a 1 meter long,
> > 1 meter diameter  2 inch thick steel cyclinder with about
> >  10,000 turns of copper wire carrying ten amps of
> >  electric current  wrapped around it, with a 2 inch thick
> > 2 meter long by 2 meter wide  square of steel behind it
> > as the radiation shield. Matter antimatter annhilation
> > produces only one kind of radiation which is gamma rays.
> > A light weight material such as beyrellium metal can
> > also be used to make the gamma radiation shield.
> >Timothy J Mayes
> 
> Prove it.  How much waste heat will the engine need to stand?  All the
> radiation heading toward the shield will be come heat.  The pipe and wire
> will heat up too.
> 
> Are you sure that will be all it takes to turn your relatavistic pion stream
> toward the rear of the ship?  The magnetic feild would have to at least be
> strong enough to lift the 600,000 lb ship, since its the force transmiting
> the thrust to the ship.  Past that though it has to have more power to turn
> the random pion stream.
> 
> Thats just off the top of my head.
> 
> Kelly

Still confused here. What is "pion"? 
Are we talking a anti-matter launch vehicle here or a general purpose
space tug type engine. Will the engine design scale ok for larger 
thrust.What trust and size is optimon?
Post Blue prints!!!!