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Revision as of 18:00, 28 June 2019 by Kent Paschke (Created page with "# Measure the raster size with the 90-degree carbon hole ## With no target, establish 5 uA beam. Move beam center to center on [https://logbooks.jlab.org/entry/3695570 carbo...")
- Measure the raster size with the 90-degree carbon hole
- With no target, establish 5 uA beam. Move beam center to center on carbon hole location
- turn off beam. Move in C-hole 90deg target.
- turn on 20 nanoAmp beam. Set raster to current units.
- run spot++. verify that raster (4mm x 6mm in reality) is (approximately) appropriately filled by the 2mm diameter hole.
- remove the C-hole target
- Prepare beam for Lead target
- establish 1 uA beam (with no target)
- move beam to collimator center 4A(x,y) = (0,0) and 4E(x,y) = (0.6, 0.4)mm.
- set raster to 10x10
- set current to 20 nanoAmps
- verify that VDC and GEM detector HV are off
- Move to lead target
- mask and insert lead target
- establish 20nanoAmp beam.
- run spot++. Verify no edges.
- Set raster to nominal 6mm (width) x 7.2 mm (height)
- run spot++ (uniformity check)
- turn off S0 voltages on left and right arms.
- set to desired current. No more than 50uA.
- WATCH target temperatures, target return coolant temperature, collimator temperature, and beamline thermocouples.