17.9 Cycle 12 Calibration Plans

The Cycle 12 calibration plan continues the routine monitoring programs of Cycle 11, with reductions in observing time where less data or less frequent monitoring are now sufficient. As before, much of the program is devoted to producing timely darks, biases, flats, and sensitivity corrections, and to monitoring basic instrument characteristics and performance. Characterization of CTE remains a high priority, to support upcoming CTE correction of fluxes in extracted CCD spectra in the pipeline.

Additional or modified observations will be made to meet specific needs in some continuing programs, and some new observations will be made, as follows:

1. We expect to monitor CCD spectroscopic sensitivity somewhat more frequently so that dependence on detector temperature can be modelled more accurately, along with tracking temporal dependence.
2. Deeper MAMA wavecal exposures will be made to support physical modelling that will lead to better dispersion solutions.
3. Spectroscopic observations will be made of a star stepped along slit, achieving low signal and background levels, to improve our characterization of the large CTE losses that occur at these low levels.
4. New "apertures" (target locations in existing apertures) have been defined to improve observations high on the CCD detector (where CTE losses are less) and low on the FUV-MAMA detector (where dark current is less), and to provide a new coronagraphic aperture (see Section 2.2). The locations of the new apertures will be verified.

   If your program requires unique calibrations beyond those that are planned (use the Cycle 7-12 Calibration Programs as a guide) and that are of direct benefit to other STIS users, then you should apply directly for this calibration in your Phase 1 proposal.