STIS Instrument Handbook for Cycle 24

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10.2	Phase II—Scheduling Approved Observations

Below, we provide a checklist for observers filling out Phase II proposals. You should do the following prior to submitting your program.

For All Proposals:

•	Update the text in the Phase II template “Observing Description” and “Special Requirements”—they were copied from your Phase I proposal and may need modification based on TAC comments and definition of the observation details.

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Specify your coordinates (especially for spectroscopic observations) in the Guide Star reference frame. Be sure to specify the coordinate source used, and, if applicable, include the GSC PLATE-ID in your Phase II proposal file. If your target has significant proper motion, be sure to also include this information in the appropriate fields in the Phase II proposal file. Check that the units of the proper motion are correct, and that the epoch specified is consistent with the coordinates supplied.

•	Specify accurate V magnitude, fluxes, spectral type, and colors for your ­target. This is required for MAMA targets to allow for bright object screening.

•	Properly specify your exposures.

•	Include target acquisitions and peakups as needed.

•	Specify any needed orientation and/or timing requirements. To facilitate scheduling, please provide the broadest possible ranges for these requirements that are consistent with your scientific needs. If multiple ORIENTs are possible, please include the alternatives.

•	Specify any allocated coordinated parallel exposures.

•	Include any additional wavecal exposures if needed.

•	Verify the correct usage (i.e., direction) of your PATTERN optional requirement or POS-TARGs (if used).

•	For slitless spectroscopy or prism observations, remember to take an image and the proper calibration sequence if needed.

•	Check the Phase II webpage for any updates. You can also find there instructions for requesting changes to your program and observing policies.

For CCD Observations:

•	CR-SPLIT CCD exposures, as appropriate. Keep individual exposure times < 1000 s if possible to avoid excessive cosmic ray events.

•	Add fringe-flat exposures for G750L and G750M observations at λ > 7500 å.

•	Consider the use of dithering for imaging observations, or stepping along the slit for spectroscopic observations.

•	Consider whether moving the target closer to the CCD readout by using the E1 pseudo-aperture positions to reduce charge transfer efficiency (CTE) effects would benefit your program. If observing in the far red, consider the E2 pseudo-apertures to improve fringe removal.

For MAMA Observations:

•	Re-verify that your target falls below the bright object limits.

•	For TIME-TAG observations, verify the value for BUFFER-TIME.

•	Consider the use of dithering for imaging observations.

•	Consider the use of stepping along the slit for first-order modes or the use of FP-SPLIT slits for echelle modes, when high signal-to-noise is required.

•	For faint objects, consider using the D1 pseudo-apertures to mitigate the FUV-MAMA dark current.