SPARO loadcurves- August 25, 1998
During the last cooldown in August, load curves were taken on SPARO's bolometers
. The purpose of these loadcurves was in part to determine which of the
detectors were working properly. In addition, by comparing our load curve
results to those experienced by others, we can use the load curves as an
indicator as to whether there are any excessive light leaks in the SPARO
cryostat and also whether the current filtering schem is adequate.
This load curve was taken on the detectors in SPARO's R-array. Data are
missing for D7 because its jfet is believed to be faulty.
this load curve was taken for R-array detectors as well. In this case the
Blank off wheel was open. Notice that the additional radiation load makes the
bolometers more sensitive to incident currents(i.e. it takes less current to
heat the bolometers)
In the T-array, detector 5 has an open circuit at the bolometer and D8 and D9
are not working for unknown reasons. Here are the load curves for the
closed blank off wheel.
These data were taken for an open BOW:
