Hallc beamline fsd guide

Qweak

Only Hall Leader (or in his absence Greg Smith) can give permission to mask the FSDs. The only exception is masking target motion which any trained target operator can give permission for masking.

Below is guidance for the Hall Leader about the possible conditions and who to consult when deciding to mask beamline FSDs.

• Beam exit Window Flow/ Dump Chiller : Cannot be masked
• Tungsten Plug : Should only be masked in unusual circumstances, since there is a danger of forgetting to unmask. Ok to mask when run at less than a nA. Consult Greg Smith and Roger Carlini.
• Liquid Hydrogen Pressure: Only can be masked when target is warm or out of beam. Consult Greg Smith and Silviu Corvig.
• Combined raster/beam current: Rare to need masking once the experiment is running. Consult Greg Smith and Roger Carlini.