Log entry time 02:22:20 on June13,2004

Entry number 125517

The raster/current scan taken earlier appears to show significant
density fluctuations.  Bryan is undertaking analysis and will have 
results soon, from which we can choose an optimal configuration.

Meanwhile, I've asked the shift crew to take all production beam 
at 4x4 raster.  If an opportunity comes up, we may want check the beam
spot on the BeO target to re-assure ourselves that we are well 
centered on the ladder (I don't think this has yet been done).
Checking that fact would make the large raster a bit more comfortable.

The most important change we can make for better production
efficiency may be fan speed.  Dave Meekins turned the fan down to
24 Hz to save overhead.  This can be changed back to 48 Hz (we won't 
be testing the power limit of the target, which is at 50 uA, given
the limits from the septum).  We will lose some of our comfort zone 
on the target if we do this, and given that we have had 3 vents of the
target in the first 24 hours of operation, it doesn't seem like a 
good idea to play any games right now. (We have enough Helium for only
one more target refill, so we should keep our fingers crossed.)
Also, right now, we don't have control of the fan speed; I believe
some control unit downstairs requires a reset (if I understood
Dave correctly).