Good Evening-
Things went well, but not exceedingly so, today. This morning, the RGA head on
tank 4 was found to be non-functional. The tank was let up, a new head put on,
and pump down began again shortly after lunch. Ion pumps have been exercised,
but the vacuum will not be good enough for RGA until Monday morning. On the
upside, the tank has been thermally cycled once.
    Tank 1 was cooled down by 1600 today and an RGA run done with the the lN2
disconnected and helium flowing through the cryo piping. Initial indications are
encouraging! RGA runs were done with the helium pressure as high as 40psi. No He
lines were seen on the RGA although there was a hint (only a hint) of an
increase in pressure with the RGA in leak detector mode at 40 psi (only) -
perhaps because the tank was beginning to warm up? Runs were done at 5, 10, 20,
30, and 40 pounds. As this is being written, tank 1 is being warmed to 200
Kelvin with warm (140 degF) nitrogen gas. Henry and Hal are sticking around
until then and will re-plumb the tank for its second cooldown. Early morning it
will be warmed again. If the second RGA looks good, a third thermal cycle will
be foregone (is this a word?) and the tank prepared for installation. The RF
feedthroughs need to be checked, the cryo amp boxes installed, cryo piping
modified back to normal running, etc.
    Meanwhile, tank 4 will be cooled down as soon as the plumbing is available
and then RGA checked. Considering the repair done to this tank, I believe it is
in our best interest to do a full three thermal cycles. The cryo guys tell us
that they typically perform three such cycles on their components.
   Wednesday looks possible for baking. The vacuum guys continue to do an
outstanding job in my estimation. Great care is going into making sure the tanks
are being put back together properly and thoroughly tested.
    I get to spend Monday at the Kane County Courthouse as I have received a
Jury summons and have been ordered to report Monday morning at 0800. Dave McG
will keep tabs on and report progress.

Regards,
elvin