Daily Archives: March 18, 2010

Dependencies

With our large project and small team, at any given time each of us has a to-do list longer than we can read in one sitting.  For the most part, we each choose tasks to work on based on mood or momentum.  In the last few days, though, I’ve been trying to determine which of our myriad of checkboxes is limiting our progress towards the distant but looming goal of flight readiness.

The two most immediate items on that prioritized path are finalizing the detector connections and installing the shields.  Our heavy bismuth germinate (BGO) shields surround the NCT detectors on the bottom and the sides, reducing background from the atmosphere.  Installing them is a risky and dicey procedure, though, so we want to make sure our detectors are behaving as they should and the connections are all good before we wall them off.  All this takes time, consultation, and reference to archival data.  We’re making progress, but it’s not as clear cut as determining that things turn on.

For their part, the shields turned on fine, but we found higher background rates than we expected.  With ground backgrounds poorly characterized and influenced by everything from the presence of smoke detectors to the composition of the hangar cement, sorting this issue out has been a headache.  So far, though, careful tests by Jane and Zach suggest the shields are working as they should.

Steve has been busy building an electronic isolator to report the cryostat temperature.  Alfred and Ming-Zhe are working on the test solar panels.  I’ve made a few minor changes to the flight software, and Alan continues to improve our ground support software.  Alan and I are also discussing our calibration plans–if and when the sources we need arrive!

Keeping it all straight is a task in itself, but we’re helped by great support from team members still at home.