Run Coordinator report: Fall 2019 w5
RC summary Dec. 18th-20th 2019
On Wednesday 18th 2019, the preparation and tests for the high rate production data taking of GlueX-II were successfully completed. In the evening (about 10pm), we resumed the last part of the DIRC commissioning: about 5h of data taking at DIRC voltage of 950V and another 5h at 1050V (nominal is 1000V). The shift crew noticed that the rates were too low. After several hours of investigations, it was found that a FCal fADC module had failed. Bypassing it allowed the DIRC commissioning to restart (around Thursday 19th 5am). The plan was then to run for about 10h at 350 nA (GlueX-II current, compared to 150 nA for GlueX-I with thick radiators) with the new DAQ configuration, to see if any problem would appear. Next, investigation of the data corruption problem (with updated FADC firmware on FCal crates), a short TAC test, a ComCal anode test and the tagger accidental test were planed. However, by about 6pm Thursday, a CHL crashed, followed by another CHL crash. The CEBAF ops group then proposed to extend the run to Friday noon instead of Friday 8am to compensate for the lost time. We adapted our runplan and counting room staffing to the new schedule. The beam came back around 4am Friday but went down again at 5:30am due to a a 2nd pass separator failure compounded with a RF cavity trip in south LINAC. At that point, it was decided to conclude the Fall 2019 run. Of the tasks planned during these few days, we could only finalized the DIRC commissioning, run about 3h at 350nA in GlueX II production mode, and test the new FADC firmware (successfully: it seems to be free of the corruption issue). The TAC run, the ComCal anode current and the tagger accidental test could not be done. We had about 15min of 900 nA in the Hall Friday around 5:20am for this latter test, but the beam disappeared just has Richard Jones was done with finalizing the parameters for the test and be ready to take the data.
Despite a rocky start and finish, the Fall 2019 was very successful for Hall D. We had two important goals: fully commission the DIRC, and testing our equipment, including an alternate DAQ software (cDAQ), at the high rate of GlueX-II. Both goals achieved successfully, including straight track runs and the use of a small GEM/TRD device with an adapted trigger for improved tracking information for the DIRC. Other tests were done successfully: preparing/establishing good running condition for the GlueX II run of Spring 2020, enabling a FCal-BCal-ST trigger and do a short Charge Pion Polarizability (CPP) test. Non-Invasive work in the Pair Spectrometer area was conducted to test the EIC/Hall C aerogel and new glass-scintillators. Other tasks could not be done: the TAC run (later downgraded to a shorter test), the full CPP test, a ComCal anode current study, the tagger accidental test and to gather enough data for physics analysis.
We are in good shape for a prompt start of high luminosity GlueX-II production early January.
