Subject: HRI-SIM TV2 Flash report Date: Sat, 17 Aug 2002 21:31:34 -0400 From: Dennis Wellnitz Hi all, This morning at 7:30 am we began the conversion from liquid nitrogen to liquid helium cooling of the cold plate. We met at 9:00 am to plan the day's activities, which we then carried out. We checked the IR-FPA hourly until it came out of saturation at about 12:30 pm. By 2 pm we were able to begin alignment procedures, which continued through 7 pm. We are now closing down data taking for the night, providing some time for the detector to cool further and the SIM bench temperature to stabilize, and permitting some time to analyze the data before we meet at noon on Sunday to plan Sunday's activities. The temperature of the IR-FPA as of 7:30 pm MDT is 104 K. Already we can say that the adjustments to the spectral and spatial registration are very close to what was desired, while maintaining internal focus, and that alignment is proceeding much more rapidly than it went for HRI-SIM TV1; we have already accomplished the degree of alignment that took three days during TV1. There appears to be a good chance that we will be able to start calibration procedures late on Sunday. Please let me know if you have any questions or comments. Dennis