2.3 Use of Available-but-unsupported Capabilities

We have established a set of core scientific capabilities of STIS which will be supported for Cycle 13 and are described in this Handbook. They provide an enormous range of scientific applications.

STIS has capabilities that are not described in this Handbook, and which are not supported for Cycle 13. They include additional slits and data-taking formats. These capabilities are "available-but-unsupported" upon consultation with a STIS Instrument Scientist. If you find that your science cannot be performed with the parameters described in this Handbook, you may wish to consider use of an unsupported capability. A full list of STIS's available-but-unsupported capabilities are described in Appendix A.

Use of unsupported modes comes at a price, and they should be used only if the technical requirement and scientific justification are particularly compelling. Proposers should be aware of the following caveats regarding unsupported modes:

• Calibrations for unsupported capabilities will not be provided by STScI. Either users must determine that they can create calibration files from data in the HST Archive or they must obtain calibrations as part of their observations. The STScI pipeline will not calibrate data taken in unsupported modes but will deliver uncalibrated FITS files (or in some cases partially calibrated FITS files) to the observer and the HST Archive.
• STScI adopts a policy of shared risk with the observer for the use of unsupported capabilities. Requests to repeat failed observations taken with unsupported capabilities will not be honored if the failure is related to the use of the unsupported capability.
• User support from STScI for observation planning, as well as data reduction and analysis, with unsupported capabilities will be limited and provided at a low priority. Users taking data with unsupported capabilities should be prepared to shoulder the increased burden of the planning, calibration, reduction and analysis.

Cycle 13 Phase 1 proposals that include use of unsupported STIS capabilities must include the following:

1. Justification of why the science cannot be done with a supported configuration;
2. A request for any observing time needed to perform calibrations;
3. Justification for the added risk of using an unsupported mode in terms of the scientific payback;
4. Demonstration that the observers are able to bear the increased burden of calibration, reduction and analysis of their data.

During the Phase 2 proposal submission process, the Spectrographs group lead must also formally approve your use of an available-but-unsupported mode. This allows the Spectrographs Group to evaluate your request and ensures that no problems associated with your request have come to light since the submission of your Phase 1 proposal. We require that you summarize the above four points in a brief email message requesting approval for use of an available-but-unsupported mode.

The increased burden of calibrating data taken using available-but-unsupported modes also makes the use of such data for archival research significantly more difficult. As a result, requests for use of available modes which do not adequately address the above four points, or which will result in only marginal improvements in the quality of the data obtained, may be denied by the Spectrographs group, even if the request was properly included in your Phase 1 proposal.