Operator: akdogan
BEAM:
Beam came at around 19:30. CCR took the beam for tuning for about an
hour, and we got the beam for production data at around 20:30.
Resumed data taking. First hour of the data taking was a little bumpy; there
were too many (3-4 per fill) WC trips, and the WC scalers were around 30. It
didn't take CCR too long to fine tune the beam to what has been achieved
earlier today which was reasonable both for Blast and Compton.
Right now, the WC scalers are at around 19-20, and the dead time is about 20%
at the top beam current. Average beam lifetime is about 22min.
--- o ---
COMPTON:
Compton fine tuning has also be done: Laser/Collimator scans were done.
Absorber thickness is set to 1.5", we may want to reduce it 1.0" on Monday,
after evaluating the weekend data. The backscatter photon rate is 1200Hz/mA
with no absorber and it's about 500Hz/mA with 1.5" absorber where signal to
background rate is better than 2:3.
--- o ---
DATA:
Resumed Polarized ABS Deuterium data.
Took runs: 8127-8136.
All of the runs are being crunched.
--- o ---
PROBLEMS:
- One coda ROC communication problem. Had to issue a cold reboot in
D-tunnel.
- WC R24 tripped every 5-6 minutes at 3850V. Lowering it to 3800 for about
an hour helped a lot. Now it's back to 3850V and tripping about once
every fill, which is manageable.
- ABS alarm handler kept the lonely shift person awake by requiring a reset
frequently. The alarm (ABS:intNewOverallAlarmsoft) clears after a reset.
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:31 EST