Operators: kdow chris2 baris
Beam has been off all day due to a problem with the Master Oscillator Amplifier for the accelerator and ring RF. Defa Wang has jury-rigged a repair, and the South Hall is being searched as of 15:00.
Doug Hasell has used this time to look at the wire chambers. The boxes that would not stay on are now ok (at least, without beam). He opened them and repotted the HV connections, in case the humidity in the hall (since the 9/19 rainstorm) was getting at the HV connections.
Michael Kohl, Tancredi Botto and I have looked at the LADS with the flasher. We found that the Left 15cm wall had the HV cables for the bottom tubes reversed (1<->14, 2<->13 etc), so correct voltages weren't being applied. Also for that wall, the tube bases were swapped between the top and bottom tubes, again meaning the correct voltages weren't being applied. Once these problems were sorted out, we saw a good flasher signal on the scope from the L15 9th bar.
There was also a logic signal for LADS OR from the left sector. Comparing this to the Ohio OR, LADS comes about 16ns earlier and lasts about 40ns longer. So we didn't adjust the LADS OR delay.
The LADS scalers aren't counting, although we see pulses in the scaler cable when we go through a LeCroy ECL->NIM adapter. In fact, the scaler counts when we look take the signal from the ECL OUT of the level adapter. We suspect there is something wrong with the ECL driver in the Miro Modules; Michael will be talking with Miro about it. The same problem exists in the DCP output (for the TDC) of the Miro modules. So we don't expect signals in the TDCs for LADS until the problem is fixed. There SHOULD be signals in the ADCs.
We have NOT connected up the Ohio OR to the jumpered OR of LADS ORs (we have to run some long 2-pin ribbon cable), so the LADS are not actually in the trigger.
The plan is to open the South Hall for 7am on 9/23, for installing (and surveying) a collimator upstream of the target. This is expected to take all day.
Doug will communicate the run plan for overnight. If the desire is to try the new version of the physics trigger, the file is ~/pro2003/trigger/newphys_4C.settings. See newphys.README for an explanation of what the various triggers are.
This archive was generated by hypermail 2.1.2 : Mon Feb 24 2014 - 14:07:30 EST