Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: More on Mass Spec Analysis
Date: Aug 23, 8:05 am
Poster: Jim Lux

On Aug 23, 8:05 am, Jim Lux wrote:

>Thought a new thread should be started...
>Perhaps Richard could comment about the pump locations and whether a port for a mass spec would be practical in this area.

But aren't you in a molecular flow area... As the Lesker catalog points out "Vacuum doesn't suck".. The pump just removes any molecules that happen to bounce into the inlet (why pump diameter is everything for high vacuum). It shouldn't make any difference where you hang your mass spec.

Was also thinking about the constituents of the fusor "star" rays that are seen. These should be relatively high in concentration of fusion reactants.

The rays are mostly electrons, and because they are low mass, they are focussed well by the grids. Actually, of course, the visible part is the result of the neutral atoms in the way getting hit by the fast moving electrons, but the idea is the same.

Could some type of deflection or sampling method be positioned near the apex of the ray. Since some appear to impinge on the Fusor outer shell, a sampling port located there would be a good place to put the MS...I am rashly ignoring all sort of practical issues such as magnetic shielding and etc., ...assuming they can be worked out Comments?

that is, would it be worthwhile to make some sort of electrodes/focussing arrangement to capture the positive ions? What about neutrals? I forget, what percentage of the chamber contents is ionized and what percentage is neutral?

>Dave Cooper