The focus of Run Coordination during LS1 is to monitor closely the advance of maintenance and upgrade activities, to smooth interactions between subsystems and to ensure that all are ready in time to resume operations in 2015 with a fully calibrated and understood detector.

After electricity and cooling were restored to all equipment, at about the time of the last CMS week, recommissioning activities were resumed for all subsystems. On 7 October, DCS shifts began 24/7 to allow subsystems to remain on to facilitate operations. That culminated with the Global Run in November (GriN), which   took place as scheduled during the week of 4 November.

The GriN has been the first centrally managed operation since the beginning of LS1, and involved all subdetectors but the Pixel Tracker presently in a lab upstairs. All nights were therefore dedicated to long stable runs with as many subdetectors as possible.

Among the many achievements in that week, three items may be highlighted. First, the Strip Tracker has been operated at lower temperature for the first time, going from +4 °C to 0 °C, –5 °C and –10 °C. Global runs were also performed during each transient, to monitor movements with the laser alignment system. Second, halfway in the week, the trigger latency was increased by 0.3 μs relative to Run 1, in order to buy some time needed by the L1 trigger upgrade. These new settings will be the baseline for Run 2. Third, few runs were performed including the relocated DT sector collectors in YB–1, validating the work done in the last months and increasing the confidence for the intervention on other wheels in the coming months.

The GriN ended on a high note, with a few runs with the participation of (some fraction of) all CMS subsystems.  While the purpose was not to perform an alignment campaign, CMS still being partially opened), the exercise was also a valuable test for the offline teams in order to validate the recent changes in the reconstruction, calibration and validation infrastructure.

Looking forward, a new layout for the control room at P5 has been developed, with input from CMS Safety, from the Technical Implementation Group, and from each subdetector operation team. The design addresses all major problems, and satisfies all known constraints. Its most attractive feature is that it only requires moving furniture (and associated network and power). Improved DCS station location and a more appropriate visitor path are among the objectives. The schedule is being worked on to minimise the impact on the commissioning operations.

by Christophe Delaere