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Дата изменения: Thu Nov 25 00:45:56 1999 Дата индексирования: Sun Apr 10 00:21:10 2016 Кодировка: Поисковые слова: tail |
We have the Astrologs and the Murmur logs for every night of the run except for the night of 08 October 1999. These logs were retrieved from the GLST tapes. Kinney did an extensive search in the Murmur logs, looking for any mention of problems with the mirrors. She searched on the words ``mirror'', ``galil'', and ``focus'' and found nothing. She also found a list of people who had logged into the iop servers using the SYSLOG file and found nothing unusual, although access to the secondary can be obtained by using the TCC or logging directly into the secondary controllers. The focus-<MJD>.par files were alos looked at to compare the commanded focus position with the MIG data. This effort was seriously hampered due to the fact that the focus-<MJD>.par files do not contain time stamps. The focus-<MJD>.par files do have run numbers and frame numbers written with the focus values. The files idAstroline-c3-<run#>.par did contain run number, frame number and a time stamp in Unix system time. (Unix system time is the number of seconds from 0h 1970 January 01 in Mountian Time.) Using these files, it was possible to cut-and-paste (by hand) the time stamps into the focus-<MJD>.par files. It was then possible to plot the commanded focus position vs time. We subtracted the value 939,967,232 (the number of seconds from 0h 1970 January 01 to 0h 1999 October 15) from the time stamps, to put Figure 4 on the same time base as Figure 1 through 3. The plots of the commanded focus and MIG values for 1999 October 15 do have approximately the same shape. The left-most spike in Figure 4 corresponds to the right-most spike in Figure 2, and is the incorrect focus adjustment. A more detailed comparison of the commanded focus position vs the measured position of the secondary mirror will require knowledge of the MIG values, so we can put the plots on the same scales.