Run Coordinator report: spring 2019 w1-3

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---RC summary, Jan. 22nd -Feb. 13th 2019

The start of the Spring 2019 physics run was expected for Feb. 7th, with beam running starting on Jan. 22nd. Delays with the accelerator postponed the physics run to early morning of Feb 9th. The delay was caused by a high pressure in the North linac 4He cooling line which made its CHL to operate in unusual conditions. This also caused the C100 cavities to trip frequently, which made beam tuning difficult. Eventually, this problem was fixed and 4He processing of troublesome cavities allowed to operate CEBAF at a reasonable RF trip level. Then, the accelerator ops established very quickly a good beam to all the halls. After going through our standard procedure to check the beam quality, check-out our detector align our 17um diamond, we proceeded with the first part of the Spring 2019 program: the commissioning of DIRC. The first phases of the commissioning went very smoothly, without unexpected bad surprises. The biggest issue encountered was a problem with the DIRC SSP firmware. It was patched after a prompt but intense work by Sacha Somov and Ben Raydo. But overall, the first part of the commissioning went well and we were on schedule with the runplan when my RC tenure ended on Feb. 13th.

A notable event during my RC tenure was that on Feb. 8th the solenoid power supply motherboard failed. This delayed the solenoid ramp up, and required a access during most of the afternoon. But this did not cost us time since accelerator ops used this time to tune the beam to the other halls.