[BLAST_SHIFTS] run plan weekend

From: Tancredi Botto (tancredi@lns.mit.edu)
Date: Fri Dec 12 2003 - 21:02:02 EST


Hello,
we have temporarily solved the problem with the Fastbus crate power
supply. Power for the right sector +5 V goes to the missing left sector
power supply. Next week we should be getting spares.

We restarted production at I < 80 mA and holding field angle 45. Things
are extremely quiet and going well. Plan is continue this until monday.
There will be no possibility of operating beam spin flipper this weekend.
If things and the extracted 45 def asymmetries consistent (with compton
and summary results of last week) we should:

_ raise beam current to 120 mA (we can't go much above that and expect
  comprably well tuned beam at the same time: 120 mA is our current max)

_ if things make further progress and are still stable on sunday
  (including analysis results) it would be worthwhile to adjust the cell
  temperature to 100 K. We might have a higher polarization but stable
  conditions are required to observe it.
 
_ As time/running allows:

        _ study prescaled singles trigger (w/ and w/o CC). We need to
           update the prescale factor while keeping deadtime<10%

        _ Measure a short run with the slits OUT: one would expect a worse
          S/N background, also with a second level trigger. (if it does
          not get worse then our S/N can also be due to wch inefficiency

_ If there are problems with the ABS measure unpol/empty target.

NOTES:
***************

_ Doug is in Canada. TB is not reachable tomorrow. Call Karen if you have
FBus problems.

_ At all times we measure with 2nd level trigger, coda configuration is
PHYS2LT.

_ Monitor the ABS intensity. ABS people should leave/update
reference numbers. Right now ligit 6.4E-8 (it approaches 1e-7 when the
target is off resonance).

_ The read back from the holding field gauss probes is hopefully
(permanently) fixed. However we have lost the gain/offset parameters in
teh past at which point the measured field in megaGauss... contact vitaly

- Various elog bugs have been fixed, including email attachments...

________________________________________________________________________________
Tancredi Botto, phone: +1-617-253-9204 mobile: +1-978-490-4124
research scientist MIT/Bates, 21 Manning Av Middleton MA, 01949
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