Difference between revisions of "G2p-beam-recovery"
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# Ask for 50~100 nA beam with fast raster(use the same size as production runs, usually 2x2). | # Ask for 50~100 nA beam with fast raster(use the same size as production runs, usually 2x2). | ||
# Let MCC know your are going to turn on slow raster. Turn slow raster on with 1.8 cm radius (about 1.3V), or use the raster size of production runs. | # Let MCC know your are going to turn on slow raster. Turn slow raster on with 1.8 cm radius (about 1.3V), or use the raster size of production runs. | ||
| + | # Check to see if the BPM values on the white board matches with the ones on strip chart | ||
# Do spot++ on both arms. If the hole is not imaged in the center, adjust the beam position. | # Do spot++ on both arms. If the hole is not imaged in the center, adjust the beam position. | ||
# If necessary, do a harp scan to check the beam profile. | # If necessary, do a harp scan to check the beam profile. | ||
| + | # For 2.2 GeV beam with 2.5T target field and 50nA current, the 3rd arm trigger rate should be <2KHz. Otherwise beam is scrapping somewhere. | ||
| + | ## Check 3rd arm trigger rates on the xscaler display | ||
| + | ## Check slow raster pattern using 3rd arm: Do "spot_3" on adaq@adaql2 after starting a run. | ||
| + | ## Also inform RC or student expert in the back room. | ||
Latest revision as of 18:28, 3 April 2012
Procedure for beam recovery
Assuming MCC can deliver tune beam to the hall, here is the beam recovery procedure:
- Check "Optics Mode" in Hall A General Tools. Click right button next to Left/Right "P0 SET". It opens a new window, which contains the "Optics Mode" pull down menu. Make sure it is in the “g2p/GEp_1” option.
- Check HRS momenta and septa currents, make sure they are consistent with each other.
- Ask MCC to stop the beam, move target position to 'carbon hole'.
- Ask for 50~100 nA beam with fast raster(use the same size as production runs, usually 2x2).
- Let MCC know your are going to turn on slow raster. Turn slow raster on with 1.8 cm radius (about 1.3V), or use the raster size of production runs.
- Check to see if the BPM values on the white board matches with the ones on strip chart
- Do spot++ on both arms. If the hole is not imaged in the center, adjust the beam position.
- If necessary, do a harp scan to check the beam profile.
- For 2.2 GeV beam with 2.5T target field and 50nA current, the 3rd arm trigger rate should be <2KHz. Otherwise beam is scrapping somewhere.
- Check 3rd arm trigger rates on the xscaler display
- Check slow raster pattern using 3rd arm: Do "spot_3" on adaq@adaql2 after starting a run.
- Also inform RC or student expert in the back room.
