Make New Entry, Make Followup Entry
User name jroche
Log entry time 16:48:43 on November 5,2010
Entry number 338685
keyword=new calibration for BCM (epics values)I just updated the coefficients for the bcm epics readings using the data we took tis morning (BcmLog_165). The new coefficients (based on today's data) are IBC1H00(54.23,0.0) and IBC1H00A(51.64,0.0).
- The previous coefficients were IBC1H00(76.920, 0) and IBC1H00A(69.960,0). I am unsure when those values were last updated in the display (maybe May 20, 2010). I had not updated the coefficients in the display after we did the initial bcm calibration on October 14. The analysis of the data taken then (BCMLog_160) were IBC1H00(81.25,0.0) and IBC1H00A(75.52, 0.0).
- The figure shows the data off BcmLog_165. The top plots show bcm1 versus OLO2 (readings directly in uA). The left plot shows OLO2/bcm1 versus OLO2. We do see a sligth non linearity of the two when running at current larger than 10uA. The right plot show the values of the ratio OLO2/bcm1 for current smaller than 8uA. The bottom plots are for bcm2. Similar features are visible in the October 14 calibration.
- keep in mind that the new calibration is due to the new temperature set point for the BCMs in the Hall.
FIGURE 1
