DIRC Shift

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The DIRC is a plane of 4 independent boxes each containing 12 fused silica radiator bars with a size of 4.9 m x 35 mm x 17.25 mm, which are housed in an honeycomb shell with a thin aluminum skin. Each pair of bar boxes is optically coupled to a water-filled expansion volume, known as the Optical Box (OB). The Cherenkov photons from the radiators propagate through the water-filled OB and are detected by an array of Hamamatsu H12700 multi-anode photomultiplier tubes in each OB.

Routine operation

Placeholder for actions to be taken by shift crew under routine operations.

Checking the environment

High voltage controls


The H12700 multi-anode PMTs are operated inside a dark box attached to the optical box, which allows for maintenance of the system while the bases are powered off. An interlock on the low and high voltage to the electronics and PMTs protects the readout system from damage. A proximity sensor provides an interlock to shut off the LV and HV if the dark box is opened, exposing the PMTs to external light. A fan provides cooling to the electronics to prevent excessive temperatures inside the dark box, and an interlock will shut off the LV and HV if the fans are not operating or the temperature exceeds the safe value.

Expert personnel

The individuals responsible for checking that the DIRC is ready to take data and setting its operating parameters are shown in following table. Problems with normal operation of the DIRC should be referred to those individuals and any changes to their settings must be approved by them. Additional experts may be trained by the system owner and their name and date added to this table.

Table: Expert personnel for the DIRC system
Name Extension Date of qualification
Justin Stevens 269-7237
Wenliang (Bill) Li 269-XXXX