Addendum to the Minutes

I had a couple remarks regarding the minutes you distributed. One is "quibbling" - can we start calling things by proper terminology - e.g. the "focussed" cesiator?. There is no focussing - it is an apertured cesiator. Within the group, we all know what we are talking about, but to the extent that many others receive the minutes, who decidedly do not know what we are talking about, it is better to use terminology which is as technically correct as we can. (I have been bitten by this more than once.)

Secondly, and more importantly, regarding the business about building a second gun. The item as it came up, at the very end of yesterday's meeting, carried with it the notion of building a gun identical to that presently in use. To me, there are multiple issues. One is to have a test vehicle as realistic as possible, and another is to construct a gun which would not have the weaknesses of the present gun. I strongly believe simply duplicating the present gun would be unwise. However, making a test vehicle which looked very similar to PART of the present gun might make good sense. This would not be nearly as expensive as duplicating a full gun like the present one. for example, we could make a chamber which would allow testing of several ideas (e.g. Kevin's idea of inserting a cesium shield to keep cesium from areas we don't want it; my notion of keeping cesium out of harm's way by doing the cesiation within the ball; adding a means to prevent ions from striking the cathode while doing HV processing; etc., etc.). It is not necessary to build a full copy of the present gun to realistically test all of the above features. There is no substitute for actual operation at 500 kV, so we would have to do this in the Injector Test Cave, where we have a supply available. So, at least for me, I am NOT in favor of building a "second experimental gun", but rather in building a test vehicle which would be used to evaluate changes/improvements to be incorporated into a second, and better, gun. Furthermore, I do not think we presently possess the knowledge to allow us to design an improved gun. Tests should come first.

And, finally, I wish to continue to emphasize that some of this stuff is not all that quickly executed. To the extent that we attempt to make improvements fast, rather than wisely, we are likely to get what we deserve. Which is not to say that we shouldn't attempt to make improvements to the present situation, only to say that doing things right, and based on real understanding, takes time.

Finally, finally, it is not clear to me that it makes all that much sense to procure parts for an additional apertured cesiator, given the present fiscal restrictions. Cesiators don't "break" very often, and generally it isn't very involved to recapture components from an earlier design when making further changes. Until there is more money than aaaat present, buying a full set of spare components only restricts further our ability to test additional ideas.

March 4, 1999 Minutes