Make New Entry, Make Followup Entry
User name deng
Log entry time 23:47:41 on December 3,2009
Entry number 304494
keyword=explanation why we did twice flipper for slug 17, HWP INIn entry 304302 (5:45 Dec3), we changed the half wave plate to be out from IN. The current pc voltages at that time (for HWP IN, see plot 1) pc pos = 8.087, pc neg=6.613 was written to IHWP.IN for the next flip back. Till now, the pc settings for both hwp in/out are correct.
Then in entry 304353 (12:49, Dec 3), we kept the half wave plate to be out but slug number increased to 16 (from OUT to OUT). The pc voltage before flipping (HWP OUT, pc pos = 7.715, pc neg= 6.985) was written into IHWP.IN file for the next flip back (plot 2), which is obviously wrong.
After editing the IHWP.IN from PC pos= 7.715, PC neg=6.985 (before) to now PC pos=8.087, PC neg=6.613, we did flipper again, see halog 304488 and follow up entry 304489. Now everything is OK.
FIGURE 1
FIGURE 2
