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September 18, 2014 FDC+CDC meeting


  1. DAQ
  2. CDC update (Mike)
  3. FDC update (Vlad, Lubomir)
  4. Electronics (Fernando)
  5. Engineering
  6. Commissioning Wiki Page (all)
  7. Other

Instructions for Bluejeans meeting connection

FDC meeting ID: 290664653


Participants: Curtis, Naomi (CMU), Eugene, Fernando, Dave, Mike, Chris, Simon, Vlad, and Lubomir (JLab).


- Lubomir: running for a first time with sparsification in mode 1 (almost three days on gluon49), and today started also mode 8. The data make sense, Mike also looked at the pedestals, amplitudes and the timings in mode 8 and they look reasonable.

- About 10 fADC125 modules report timeout errors from time to time. Two modules, ROCFDC9-slot 14, and ROCCDC4-slot 16, crashed the DAQ. Cody already looked at ROCFDC9 and replaced the module.

CDC update

- Mike: One LV channel is tripping (by the controls) due to "overheating". That started after the power outage. We may replace the module, or first relax the temperature limits in the controls. Several CDC channels are questionable, will work on them.


- Fernando: Contacted CAEN on the noise issue, they are working on it. First article on the f125 boards (not populated) arrived, they look really nice, even the company made a cut in the board to see the quality of the internal layers.


- FDC was surveyed without field on Wednesday. They could see only two (out of four) reflectors on the first package, which unfortunately is not enough to define a plane. The reflectors on the other packages were visible. Today (Thursday) they were looking in one direction with three reflectors, while the magnet was powered to 1000A, and found 1mm shift downstream along z on all the three points. Then they moved to another position with four points visible. While the magnet was going down to zero amps, they found same 1mm shift in the opposite direction.

- The explanation: it is the whole magnet shrinking (when the current goes up) that causes this shift w.r.t. floor. The BCAL rails are attached only at the upstream side that is why it moves downstream.

- The shift is not big, but good to know. It means the target (attached to the platform) will move w.r.t. FDC with/without field. We may be able to see this with the tracks.