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BPM Status. Pengjia Zhu 2013.9.11. 3.13. 3.14. 3.6. 3.9. 3.17. 3.27. 3.29. 2.5T 90 deg. 5T 6 deg. straight through. 2.5T 90 deg. septum fired. 2.5T 90 deg. 2.257GeV. 3.17 run 3273 raster size calibration. using 3.14 constant. BPM A. BPM B. BPM A constant works good.
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BPM Status Pengjia Zhu 2013.9.11
3.13 3.14 3.6 3.9 3.17 3.27 3.29 2.5T 90 deg 5T 6 deg straight through 2.5T 90 deg septum fired 2.5T 90 deg 2.257GeV 3.17 run 3273 raster size calibration using 3.14 constant BPM A BPM B BPM A constant works good BPM B constant destroyed
Reason: div changed from 4 to 2 for both BPM A and BPMB after 3176 run -> gain changed (auto gain, gain diff between + and - did not change) (I was thought the div will not change the position) BPM A seems was not affected BPM B tragedy
3.13 3.14 3.6 3.9 3.17 3.27 3.29 2.5T 90 deg 5T 6 deg straight through 2.5T 90 deg septum fired 2.5T 90 deg timeline auto gain 3.14 straight through harp scan 3.16 2.5T harp scan 3.16 harp scan have 3 runs with div=2 for BPM B (with target field) can use BPM A and harp05 to calibrate BPM B harp 05 Luckily... BPMA BPMB
survey uncertainty -> 0.25 mm BPMA resolution limit ~ 0.15mm BPMA,BPMB,Harp are close (941,814,677mm) three harp scans' pos too close ~ 1-3mm pos got from BPMA and harp05 BPM B data The calibration failed Unfortrantly...
New method to calibrate BPM -- brute force calibration
first step BPMA Reliable BPM A position beam position at target got from carbon hole ~ 0.4mm uncertainty at target center position at BPM B
visually see the changes ideal shape radius and center position from BPMA and carbon hole check if rotation changed only raster x turn on only raster y turn on calibrated BPM B shape sliders,manualy change constant packaged used: pyQT, matplotlib
raw shape -- with 3/14 calibration constant ideal shape check if rotation changed only raster x turn on only raster y turn on BPM B shape
3185 x position at target by using new constant matched with Chao's fit result
Another job for beampackage: Optimized bpm calibration code, much faster Futher optimize: Use circle fit to get carbon hole center position instead of eyes Parameter to judge if circlular?