Difference between revisions of "Minutes-8-21-2014"
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== Engineering == | == Engineering == | ||
− | - Bill: the | + | - Bill: problems with the chiller on Monday, it was not regulating the temperature. Tom adjusted the thermostatic valve and it started regulating again. Bill discussed with the company the chiller problems. They say the thermostatic valve must be OK, but the new compressor installed is not quite the same as the original one. They don't have spare units and they don't make visits to fix the chiller. If the problems continue, either we have to swap the compressor, or send the chiller to Indiana for repair, or get a new one from Japan. The plan for now is to install the heat exchanger (maybe tomorrow) and continue monitoring. |
− | - | + | - On Monday when the chiller failed, Wesley Moore was working on the epics communication with the device. According to Hovanes he changed the set temperature to a lower value for as short time, then the chiller failed. The plan is just to read the epics variables, and not to write anything to the device. |
− | - Luke | + | - Luke: we installed the encoder and started measurements at the last position, but in the middle the encoder stopped working. In addition motor got disconnected from the stage; the set screw got lose. |
== Commissioning == | == Commissioning == |
Revision as of 19:55, 21 August 2014
August 21, 2014 FDC+CDC meeting
Contents
Agenda
- DAQ (Beni)
- CDC status Curved Tracks (Mike, Beni)
- FDC status scattering event, horizontal shower event (Lubomir)
- Electronics (Chris, Nick)
- Engineering (Bill)
- Chiller
- Cathode scan (Luke)
- Commissioning Wiki Page, CDC, FDC commissioning plan (all)
- Other
Instructions for Bluejeans meeting connection
FDC meeting ID: 290664653
Minutes
Participants: Curtis, Naomi (CMU), Sean (NU), Beni, Mike, Luke, Eugene, Chris, Nick, Dave, Bill, Fernando, Sergey, Vlad and Lubomir (JLab).
DAQ
- Beni: testing the latest fADC125 firmware released, works except something goes wrong in the FPGA when setting event number. ROCFDC3 has problems will be excluded for the next run. We want to take data with the magnet on. The top scintillator paddle was moved as high as possible to reduce the filed on the PMTs. Actually, after the meeting Beni and Elton were able to get signals from the scintillator (after increasing the HV) and started the DAQ (FDC+CDC) with the considence trigger.
- Discussions about horizontal trigger. We need to install it back. The upstream paddles can be installed when the traget is out. Instead of the downstream paddles one can use the TOF, but it requires the GTP.
CDC update
- Mike showed curved tracks (linked) in the CDC at 600A magnetic field. Some local curvatures seen can be explained if the drift time is taken into account.
- Fernado: additional ground on the CDC aluminum ring to which the HV is connected has been installed. Expect to reduce the noise significantly. Grounding the HVBs directly will be done as a last resort in it will be done in a different way through the grounding lugs.
FDC update
- Lubomir: by applying timing cuts on the hits from the two cathodes and the wires in a cell, one can reduce the threshold down to 50 fADC units (~4mV). As a result we see now most of the "missing" cathode channels, that have problems with the conductive tape. Of course the resolution will be deteriorated but one can stiil use this information for the pattern recongition. Couple of interesting events are linked above.