Tune Electron Beam

Tune Electron Beam (Time estimate: 15 days)

• Goal: provide a clean electron beam through the center of the beam aperture to the beam dump in the tagger hall with acceptable radiation levels.
• Priority: High
• Link to the accelerator test plan for electron beam commissioning (ATLIS)
• Expected duration:

1. Sept 19 - Sept 29: Tune beam to Hall D line dumplette (Tagger Hall can remain open).
2. Sept 29 - Oct 3 2014: Tune beam to Tagger Hall D (Tagger Hall and Hall D must be closed).

• Prerequisites:

1. Tagger microscope (TAGM) and all the crates with electronics removed from Hall D. $\Box$
2. Goniometer in the beam-open position. The goniometer will not be used during the 2014 run. ☑
3. Amorphous radiator ladder equipped (HARP included) and operational $\Box$
   • Responsibility: Hovanes Egiyan.
   • Procedure for radiator harp scans
4. Beam lines under vacuum $\Box$
5. Tagger magnet operational $\Box$
   • Responsibility: MCC
6. Shielding walls installed $\Box$
7. Radiation monitors installed and operational $\Box$
   • Responsibility: Alexandre Deur (CARMS)/Hovanes Egyian (halo counters)
   • Procedure to monitor CARMs
   • Procedure to monitor Halo Counters
8. Primary collimator block in the position between two holes, shielding the central area of the beam pipe $\Box$. Secondary collimator removed. ☑
   • Responsibility: Hovanes Egiyan.
   • Procedure for moving Primary Collimator
9. First Profiler counter installed in front of the collimator $\Box$
10. Second Profiler counter installed in front of photon beam dump $\Box$

• Conditions:

1. Pulsed beam pulsed beam 4-10 µA (average 60-150 nA) for the beam tune
2. CW beam 50-100 nA at the final stage of the procedure
3. No radiator inserted. $\Box$
   • Responsibility: Hovanes Egiyan.
   • Procedure for inserting/removing amorphous radiators
4. Hall D controlled quadrupole MQPAD00 turned off. $\Box$
   • Responsibility: MCC
5. No shift workers in Hall D except for Shift leader if needed and experts from Hall D are involved with the radiation measurements