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The design dispersion at the screen is 111.7mm which means the calibration should be 10.0 GeV / 111.7 mm = 89.5 keV/um. The difference between the measured and expected could be due to the screen calibration. No calibration images ever appear in the elog. The calibration starts at 17.94 um/px when the camera first appears on one of the FACET-II camera server. The calibration then changes to 9.91 um/px starting with this elog entry, but no calibration images appear in the e-log, this value as been was used for all of FACET-II. The value matches the value used at FACET, most likely the old FACET value was used without every taking a new calibration.
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