G. Moreno, K. Ryan, J. Worden, R. Weiss
A preliminary report of the procedure is given here, a more thorough report will be made once the post injection
charge measurements have made.

We introduced both positive and negative ions of N2 into the ETMY chamber. The input gas was boil off from liquid nitrogen which was additionally passed through a liquid nitrogen trap before entering the ionizer. The conditions in the ionizer: pressure
on the needles 210 to 303 torr, pressure after the apertures was a maximum 45 torr when the chamber was at 42 torr. We stopped the
process after the ionizer had become too cold to be comfortable with a elastomer O ring at the needles. (We should have
a second heat exchanger to warm the gas back to room temperature before entering the ionizer to avoid the cooling.)
The various times: start to stop of the ion injection 29 minutes, roughing pump down time after the injection to reach
1 torr about 3 hours, pressure now 3.5 x 10^-7 torr after 5 hours of turbo pumping.

A disappointment of the procedure was that we were never able to achieve equal injection of positive and negative ions, 
the sampled ion current was: i+ = 4 x 10^-9 ampere, i- = -1 x 10^-9 amps. The injected currents are about 100 times larger.
It requires tuning of the pressure on the needles and the flow rate to achieve equal positive and negative currents. If the total
gas flow is too large one cannot get to the proper tuning. This was the case today. RW made a mistake in fully opening the
gate valve between the chamber and the ionizer before tuning the system in an auxiliary flow to a pump and then gently
transferring the flow between the pump and the chamber. 

There is a reasonable chance that enough ions did enter the chamber to neutralize the etmy. The success or failure should be known shortly after the morning meeting. If the neutralization has failed we could try again today. The times are shorter than
estimated.