18:01 AFP Test with correction coil OFF 42.61 - 40.23 (42.97 - 40.69) -> 0.72% (0.68%) |0.70%|
18:09 AFP Test with SMALL CORR 0.53A, LARGE CORR 0A, 38.70 - 34.94 (39.27 - 35.40) -> 1.28% (1.30%) |1.29%|
18:16 AFP Test with SMALL CORR 0.25A, LARGE CORR 0A, 34.93 - 33.33 (34.79 - 33.52) -> 0.59% (0.47%) |0.53%|
18:28 AFP Test with SMALL CORR 0.20A, LARGE CORR 0A, 32.61 - 31.53 (32.77 - 31.42) -> 0.42% (0.53%) |0.48%|
18:36 AFP Test with SMALL CORR 0.10A, LARGE CORR 0A, 30.82 - 29.64 (31.05 - 29.65) -> 0.49% (0.58%) |0.54%|
18:44 AFP Test with SMALL CORR 0.18A, LARGE CORR 0A, 29.21 - 28.08 (29.00 - 28.02) -> 0.49% (0.43%) |0.46%|
18:51 AFP Test with SMALL CORR 0.18A, LARGE CORR -0.50A, 27.95 - 26.70 (27.92 - 26.43) -> 0.57% (0.68%) |0.63%|
18:59 AFP Test with SMALL CORR 0.18A, LARGE CORR -0.20A, 26.03 - 24.87 (26.03 - 25.05) -> 0.56% (0.48%) |0.52%|
19:09 AFP Test with SMALL CORR 0.18A, LARGE CORR 0.20A, 24.43 - 23.37 (24.26 - 23.51) -> 0.55% (0.39%) |0.47%|
19:17 AFP Test with SMALL CORR 0.18A, LARGE CORR 0.50A, 22.88 - 21.95 (22.66 - 21.94) -> 0.52% (0.40%) |0.46%|
19:23 AFP Test with SMALL CORR 0.18A, LARGE CORR 0.80A, 21.54 - 20.86 (21.63 - 20.57) -> 0.40% (0.63%) |0.52%|
Same as we expected from our field mapping. The large correction coil basically has no effect on the AFP loss since the gradient on that direction is already very small. Small correction coil plays a major role here. We finalize our correction coil currents for transver - field direction as following:
Small Correction Coil: 0.18 A Large Correction Coil: OFF
AFP loss is improved from 0.70% to 0.46%
A copy of this log entry has been emailed to: jpchen@jlab.org