Operator: akdogan
Had some beam problems during the first hour of the shift. The WC scalers
were around 100 at the top of the fill, reducing barely to 30 after 5 minutes or
so, and injection was not as smooth. Requested to reduce the injection
current from 170mA to 160mA, which seems to be working noticably better.
Noticed that the ligit jumps periodically (see elog 30571) by a factor of
two and returns to normal after a few minutes. And, just noticed that,
rather curiously, this periodicity is in sync with the end of runs. The
only effect that I can think of is the rungate. Does it effect the ABS?
Or could it be because of some electronics cross-talk?
Other than these, took ABS H2 data smoothly, with 48deg target angle.
Had a few WC trips, and a few crate-1 trips.
Beam polarization is at high 60s, close to 70% (note that the systematic
error may be slighly higher than usual, which will be addressed during the
next maintenance day). After, the laser&collimator scan the false asymmetry
went down back to zero (0.0+-0.9% for the last 7 hours).
Both left and right WC TDC spectra looks good/flat. The right sector has
a little more background.
All runs are being crunched. We should get better (lower error) target
polarization results by tomorrow.
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:32 EST