[d2n-analysis-talk] BPM Calibration Discrepancy: BigBite vs LHRS

[Vincent Sulkosky]

Dear Diana,

My first guess is that the BPM pedestals between the left HRS and BB arms 
are different.  This can definitely be the case, since we are using two 
separate sets of electronics.  We typically do a BPM pedestal run at some 
point early in the runb.  If it exists you should find it and analyze the 
data to get the BPM pedestals for the BB database.  On the other hand, 
Bodo's web page says it is not necessary and the pedestals can be taken 
out in the fits.

I suspect this is what has caused the difference.  The important question 
is do the beam positions from BB and the Left HRS agree after calibration?

Best Regards,
Vince

--

Vincent A. Sulkosky, MIT Postdoctoral Associate

CEBAF Center F358
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