Run Coordinator report: Summer 2020 w7
The plan for the week was GlueX-II production, an empty target run, and two planned tests: 1) tuning of the trigger for the Short Range Correlation Experiment (A. Somov), followed by about of shift of data taking with this trigger; and 2) testing the beam rastering method to measure the photon beam size at the collimator (R. Jones).
The empty target run was done on Friday 11th (the data taking was split in two runs due to a long accelerator down time in between). The two planned tests were successfully conducted. The SRC trigger tuning and SRC data taking were done Saturday evening. The raster test was done during Monday night. That test was successful but the many beam trips caused by the rastering makes this method less promising than hoped. It is not clear at present whether the method will be used or not. In addition to these planned tests, RCDB/DAQ tests were carried on (Dmitry Romanov and Sergey Furletov) to study how to shorten the stop-run duration.
Gluex data production was only moderately good during the week due to large accelerator unavailability: on the 159h of scheduled time, only 78h of beam were available (we used 72h). The issues were the following (in time order): the large amount of beam trips on Wednesday/Thursday decided MCC to do RF recovery on Friday 11th. It went well but it was followed by linac and vacuum problems, resulting in 18h of down time that Friday. On Saturday, the beam as down 2.5h due to a klystron change. On Sunday, the beam was down for 15h due to a chopper problem followed by a cavity issue. On Monday beam was unavailable for 11h due to 7h of planned beam studies and a 4h power supply failure. On Tuesday the beam was down for 14h due to a failure of the 4th compressor controller in CHL for the South Linac.
Because the beam was down for several long periods of time, we had several opportunistic accesses to the Hall and tagger. Most of them were in the PS area where detector components are tested. A couple of crates for the standard GlueX equipment needed to be rebooted.
