Run Coordinator report: Spring 2018 r16

Run Coordinator report, April 25 - May 2,

We were scheduled for 160 hours of CW beam, of which 124.9 hours (78%) was delivered to Hall D. Of this, we used 118.1 hours (ABU), or 74% of the scheduled beamtime. Around three hours of our unused beam was due to DAQ problems, with a further hour associated with configuration changes related to high intensity DAQ tests that were performed during the week in conjunction with the CODA group. The remaining unused beam was due to our normal configuration changes between diamond orientations and the amorphous radiator.

We have now collected 105% (1084.0h) of our expected data for the spring 2018 run, versus 92% of the schedule. This is mainly a consequence of the extension to the run, and efficiency of the machine exceeding the expected 50%, but is still a notable achievement, given the machine issues that delayed the start of our run back in December.

Detector performance was excellent overall, although some accesses were needed to continue the standard program of FCal base replacements, swapping a board for the TAGH, which eliminated a noisy channel seen throughout the run, replacing a failed card on the TOF high voltage crate, and a further test of the muon chamber. These accesses all overlapped with planned beam down periods for beam studies, and tours of the halls for assorted dignitaries.

Beam parameters were mostly good, however locking issues to the active collimator, correlated to current changes in Halls A and C were encountered, leading to large, but short lived, excursions in the y-position. The 5th pass vertical separator also began to exhibit problems, with an increase in the trip rate in the early part of the week. MCC hope to have resolved this sufficiently to continue delivering beam to Hall D until the end of the run. In better news, the fast rastering tests performed throughout the week were eventually successful, and further runs are planned before the accelerator shutdown on May 6