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Phase II Checklist

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 Checklist for GRACES Phase II (OT) programs

  • General
    • Have you selected appropriate templates from the GRACES OT library? Have you gone through the checklist in the Top-level Program Overview note and included relevant standardized notes? Add notes with information about the program and acquisition that will make it easier for the observer. Try to use the standardized notes provided in the OT Library.

    • Check that readout mode and the spectroscopic mode are clearly stated in the "set-up" note.

    • Are the integration times reasonable? Individual spectroscopy observations should not be longer than 2400sec (due to the high rate of cosmic rays). Short exposures result in large overheads from the readout of the detectors, and may give data dominated by the read-noise. Check with the ITC.

    • GRACES observation sequences that take longer than ~3 hours to execute will likely not be executed all on one night, and you must allow adequate time for re-acquisitions on subsequent nights when filling the allocated time. Have you read the details about the overhead calculations? Have you added a note explaining how many reacquisitions you have assumed for the calculation of the overheads? Taking the correct overheads into account, do your defined observations fit within the allocated observing time?

    • Have you checked Baseline Calibrations to see what is offered/required.

    • Have all observation classes been set correctly?

    • Have you considered the effects of differential atmospheric refraction on your data? Note that the guiding will be optimized at the central wavelength, minimizing the light-loss due to differential refraction at that wavelength.

    • Make sure that observations taken in Normal readmode are set up as Fast Read/Low Gain in the GMOS component, observations in Slow mode should be set up as Slow Read/High Gain.

    • Check the filter under the GMOS component. This should be set up as DS920 for 1f or HeIIC for 2f.

  • Guide stars
    • Are guide stars selected for the GMOS OIWFS? The PWFSs are not used for observing sidereal targets with GRACES in most cases. First, select the position angle mode (Fixed, Allow 180deg flip) in the GMOS component as appropriate. The automatic guide star selection service will select an appropriate guide star for the specified observing conditions. Alternatively, the PI can still choose a guide star using the Manual GS button on the OT position editor. For manual guide stars, ensure that the guide star can be reached for the selected position angle, that the guide star is within the magnitude limits for the OIWFS, and that all guided offset positions can be reached. Check that the probe arm is visible and falls within the green box in the position editor. Fix any red offset positions. The UCAC4 catalog should be used whenever possible for choosing guide stars as the magnitudes are usually reliable.

    • Ensure guide stars are stars and not galaxies.
  • Calibrations
    • If the PI requires calibrating standards beyond what is offered in the standard baseline calibrations, these must be defined, including a specific target, and time will be charged against the program for the observation. Observing class should be set to Nighttime Program Calibration. Baseline standards are set to partner calibration.

  • Acquisition
    • Note that a 1x1 binning is required for the acquisition sequence.

    • Is the ROI set to custom? Are the values Xmin=2172, Ymin=1570, Xrange=1800 and Yrange=1100?

    • Is the readout mode set to Fast Read/Low Gain?
  • Spectroscopy
    • Have you included the appropriate acquisition observations?

    • If an observation includes an unusual or non-standard acquisition (eg. blind offset acquisitions), include the appropriate OT Library standardized note in the program. The text of the note can either describe the acquisition or point to other notes within the program. Using these standardized notes should minimize acquisition errors and observers won't be surprised. See the OT library for examples of non-standard acquisitions.
    • BLIND OFFSETS: Use when targets are too faint to be acquired within 5 min of imaging.
      • Make sure that a User1 target is defined with coordinates on the same astrometric system as the science
      • Make sure the blind offset User1 star has a name, preferably something like 'Reference Star' or 'Blind offset star'
      • Offset star should preferably be within 20 arcsec of the science target. The accuracy of blind offsetting is better than 0.1 arcsec for offsets less than 20 arcsec.
      • For the blind offsetting to work, it is essential that the same guide star can be reached for the bright object and the science target.
      • Include a note in the program to warn the observer of the non-standard acquisition.
    • If your observations involve complicated alignments, crowded fields, or targets fainter than about R=18 (eg. if the target is not obvious in the OT position editor with the Digitized sky survey 2 image loaded), you need to prepare finding charts. Such a finding chart should indicate the target/s and display the orientation (preferably North up and East to the left) and scale. Finding charts should be uploaded through the OT.

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