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: