Difference between revisions of "G2p optics"

Revision as of 01:05, 4 March 2012

Summary of Optics Plan

Define the following jobs:
 A. Acceptance calibration, sieve out, rasters on and off (large C12, no LHe) 
 B. Delta scan, (sieve in, C12, no LHe) 
 C. Beam position scan (Sieve in, large C12, no LHe, 8 points on x,y axis and 4 additional points at corner) 
 D. Pointing (Sieve in, CH2, need to refill LHe)

1. 0T @ 2.257:

Do A, move sieve in, do B and C(12 points), refill LHe do D.
At the end take elastic NH3 data to check NH3 thickness.
When finish: move sieve out; Ramp field up to 2.5T; Drain LHe

Operation Log

Real beam energy is 2.25365(set) and measured 2.2533 Liquid helium is not allowed to drain out to expose the target. BPM calibration is finished, cross hair scan is done. Beam is delivered to (x=0,y=0)

1. Preparation:
   1. Escorted Access to insert Sieve Slits.
   2. Cycle Q2 and Q3, set HRS momentum to 2.251 GeV/c, Change to C12 target
   3. Tune septum, start from 810A till 660A, 15A each step, expected value: 730.3A
   4. Tune quardroples, change it to: +2%, 1%, -1% -2% (Min will provide more details)
2. Escorted Access to insert Sieve Slits.
3. Delta scan.
4. Beam position scan
5. Escorted Access to move Sieve Slits out. Do acceptance calibration: use large C12(40 mil) foil in the 6th cell, rasters on and off
6. Refill liquid helium. Escorted Access to insert Sieve Slits.
7. Change to CH2 target, do pointing

2. 2.5T, 90deg @ 2.257:

Do A, move sieve in, do B and C(12 points), refill LHe do D.
When finish: Ramp field up to 2.5T; Drain LHe out

3. 5.01T, 6deg @ 2.257:

Do B and C(8 points), refill LHe do D. 

4. 2.5T, 90deg @ 1.706:

Do A, move sieve in, do B and C(8 points), refill LHe do D.
When finish: Rotate target field to 6 deg; Ramp up to 5.01T; Darin LHe out

5. 5.01T, 6deg @ 1.706:

Do B and C(8 points), refill LHe do D
When finish: Move sieve out; Rotate target field to 90 deg; Ramp up to 5.01T; Drain LHe out

6. 5.01T, 90deg @ 2.257:

Do A, move sieve in, do B and C(8 points), refill LHe do D.
When finish: Turn off target field; Drain LHe, move sieve out.

7. 0T @ 1.159:

Do A, move sieve in, do B and C(8 points), refill LHe do D.
At the end take elastic NH3 data to check NH3 thickness.
When finish: move sieve out; Ramp field up to 2.5T; Drain LHe out

8. 2.5T, 90deg @ 1.159:

Do A, move sieve in, do B and C(8 points), refill LHe do D.
When finish: Ramp field up to 5.01T; Drain LHe out

9. 5.01T, 6deg @ 1.159:

Do B and C(8 points), refill LHe do D.

• Detail G2P|GEP optics plan

For commissioning:

• Procedure suggested by Vince
• Procedure suggested by Jin