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User name V. Sulkosky
Log entry time 11:00:22 on November 05, 2008
Entry number 246861
keyword=BPM Calibration CompletedI have finally finished the analysis of the BPM calibration. The process
ended up being a lot more involved due to the quality of the data.
Figure 1 shows the BPM A and B x and y positions calibrated against the
Harp scans from the bulls eye scan taken last Wednesday. I have updated
all BPM and raster databases for the online analysis and for spot++.
Figure 2 shows the beam positions for run 2853 with the obsolete
calibration constants. Figure 3 shows the beam positions with the new
coefficients.
For this calibration, I did not use the Harp A X position, since there was
a 1 mm offset compared to all the previous data taken last year. Instead
I used my fit of the Harp A x position versus EPICS BPM A x position, which
I believe to be a more reliable number until the harps are resurveyed.
Here are the new coefficients:
BPMA constants:
-0.738959 0.759596 0.758844 0.747731 -0.000311576 0.00109736
BPMB constants:
-0.686875 0.737689 0.735834 0.691631 -0.00100634 0.00228915
A copy of this log entry has been emailed to: brads,jiang,rom
Figure 1
Figure 2
Figure 3
