Operator: zwart
Troublesome Shift.
Running polarized H after Genya switches back from Helium test.
Good runs 12144,12145,12146
BLTC's stop counting. Blast_Data_Alarm reports 0 scaler events being written. But HV GUI looks OK. Call TB who helps restart scaler app.
Large asymmetry in Compton results (+90%,-50%). Larry Loncoy adjusts electron beam position at Compton from ~ -10 mm to ~-6 mm. Adjust laser steering to reoptimize backscatter rate (mostly M3). Laser spot moves down significantly on the video monitor in the counting bay. M1 (1st remote control for vertical appears not to function). The backscatter rate increases to ~600 Hz/mA Las. Curiously false asymmetry is now almost completely inverted to (~-90%,+50%). Larry adjusts beam position to ~-7.5mm, but false asymmetry is largely unchanged. This action does however optimize the brem rate on the CsI. Normalized brem rate imroves from ~45 --> ~75. The false asymmetry still needs attention.
Should the Neutron trigger still be on if we are running Hydrogen?
Then had trouble with HV IOC. The HV gui reported "restoring", but was frozen. Rebooted the IOC and started running again.
I did not have override permission set to "off" on HV GUI. Several WC trips occured as the ring filled with HV on. Larry noticed and the HV was appropriately reset.
Finally things are smooth again.
Runs 12150, 12151 are good.
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:31 EST