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GNIRS Phase II (OT) Checklist

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There are many ways to check phase 2 files. However, for people new to GNIRS we suggest the following procedure. This assumes that the observations are set up using the OT automatic templates and/or following the templates in the OT library. NGO technical feasibility checks are carried out at the time of proposal submission, and we assume that problems with the proposed observing configuration/conditions have been sorted out by this point. For more information about GNIRS in the OT, see this page.

  1. Check the science target spectroscopy observation
    • Do the observing conditions match those specified in the proposal? If not, has approval been requested (for better conditions), and will they allow the science to be achieved (for worse conditions)?
    • Does the GNIRS component match that specified in the proposal, or will it achieve the proposal's aims anyway?
    • Will the exposure time avoid saturation and excessive sky variation/radiation events?
    • Is the appropriate read mode being used?
    • Has a PWFS2 or AO guide star been defined? Does it fit the criteria for P2 or AO guide stars?
    • Does the observation use a sensible dither sequence?
    • Is the guide star accessible at all dither positions? For large offsets to blank sky, has the guiding been set to "freeze" in the offset iterator?
    • Have flats and (except for the L/M bands) arcs been defined? The "Night baseline GCAL" option under the "Observe" menu in the OT should be used in most cases.
    • Does the sequence contain flats and arcs at multiple wavelengths? If so, is the user aware of the caution in the calibration section of this web page?
    • Are the observation classes correct? The science observation should be set to "science", and baseline flats and arcs, "nighttime program calibration".

  2. Check the science target acquisition observation
    • Is the target component the same as that in the spectroscopy observation?
    • Is this a single, easily-identifiable target that can be acquired without a blind offset? If not, or if the acquisition sequence is otherwise different from the library examples (e.g. two targets on the slit, target offset along the slit to reach a guide star), have appropriate instructions and finding charts been added?
    • Is the acquisition setup (filter, sky subtraction, blind offset, etc.) suitable for the target's brightness in the filter in which it is to be acquired?
    • Does the GNIRS component match that of the science spectroscopy, except for exposure time, coadds and read mode?
    • Is the exposure time appropriate for the target? (In most cases, the exposure times for the slit image should not be changed from the library example)
    • Are the slit and decker correct in all steps?
    • Has the observation class been set to "acquisition"?

  3. Check the standard star(s) spectroscopy observation.
    • Do the observing conditions match those of the science spectroscopy?
    • Are you satisfied with the airmass match between the standard star and science target? The "plot" button in the OT position editor can be used to check this.
    • Does the GNIRS component match that of the science target spectroscopy, apart from the exposure time, coadds and read mode?
    • Has the observation class been set to "nighttime partner calibration"?
    • Does the observation require more than the baseline standard star? If so, have the extra standards been given the class "nighttime program calibration", and an explanatory note added?
    • The above science target spectroscopy checks also apply to the standard stars, except that flats and arcs are not usually defined for standard stars.

  4. Check the standard star(s) acquisition observation
    • If this is a baseline standard star, has the class been set to "acquisition calibration"?
    • Perform the same checks as for the science target acquisition observation

  5. For imaging science
    • Follow the checks suggested for spectroscopy science and acquisition observations above, except for those referring to arc spectra
    • Does the dither pattern for the target fit into the keyhole shaped imaging field (q is the long dimension)?
    • If the PI does not intend to prepare sky flats from the science imaging exposures, have imaging flats been embedded in the science observations?

  6. Do a few general checks
    • Does the program fit within the allocated time? If not, have the observations been prioritised and/or an explanatory note added?
    • If these observations use the high spectral resolution modes at central wavelengths not covered by the automatic calibrations, has a note been added to instruct the contact scientist to check the flat and arc configurations during the day?
    • If there are spectral features of importance at wavelengths within 10% of an edge of the specified wavelength range, add a Note to the OT so that the observer ensures that the grating setting is sufficiently accurate to include them.
    • For XD observations, have daytime pinhole flats been defined?

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