GNIRS Phase II (OT) Checklist

There is a general OT/Phase II checklist that is useful to consult.  In addition, there is a NIRI page identifying a number of common OT errors most of which are not NIRI-specific.  Here is the GNIRS checklist for Phase II, of which most, but not all, are GNIRS-specific.  For more information on most of these questions, consult the Observing Strategies and OT Help pages (along with general instrument pages).

• General:
• Have you included concise and informative notes in your OT file to aid the observer?
• Have you sent finding charts to your Contact Scientist?
• Have you prioritized all your observations?
  
  
• Instrument configuration:
• Have you selected the right PIXEL SCALE and DISPERSER for the resolution desired?
• Do you have the correct SLIT WIDTH (having considered the tradeoff between slit-loss and resolution)?
• For 32 l/mm grating long slit observations, have you selected the appropriate central wavelength from the pull-down menu?
• For 111 l/mm grating, is the central wavelength set correctly?
• Is the Position Angle (PA) set, if a non-zero PA is needed?
  
  
• Cross Dispersion:  
• Is the "Yes" button under cross-dispersion selected?  
• For the 32 l/mm grating, is the central wavelength set to "cross-dispersed" = 1.65um?  (If not, explain in a note why a different value is used.)
• For the 111 l/mm grating, is the central wavelength set to the appropriate ORDER 4 wavelength?  (Use the XD tab to view the wavelength ranges in each order, but set the central wavelength window to the order 4 value for proper atmospheric dispersion correction of telescope tracking.

• Sequencing:
• Is your offset sequence set up properly?  Are offsets ALONG the slit defined in q only?
• Is your offset iterator INSIDE your GNIRS sequence (if you have one)?
  
• Have you set up you GNIRS sequence properly?
• DO ALL SEQUENCES INCLUDE AN OBSERVE AT THE INNER MOST LEVEL?
• Have you checked your observation using the "Sequence" and "Timeline" tabs at the top of the Sequence level?
  
  
• Calibrations:
• Are the appropriate baseline calibrations (flat, arc, standard star) included in the phase II file and will they be sufficient? If not, have you included additional calibration data for your program?
• Have you defined the flats and arcs as a separate observation from the science observation?  Is there a separate definition for each instrument configuration?
• Has sufficient observing time been allocated for additional calibrations?
• Have appropriate telluric standards been selected for observation both before and after the science observations?  Are there telluric observations for every instrument configuration?
  
  
• Observing time:
• Did you confirm the exposure time and S/N of all observations using the GNIRS Integration Time Calculator WITH the appropriate observing conditions?  Are the exposure times set to avoid saturation on the background and the source?
• Have you adjusted overheads to account for 1) extra overheads assumed by OT and 2) missing readout overhead?
• If many very short exposures are needed, you may need to include larger overheads to account for the lower observing efficiency.
• Are there acquisition observations for all science and standard observations?
• For short exposures, have you used coadds to add signal and limit the total number of images?
• Have you kept your individual exposure times below the maximum exposure time specific to your observing case?
• Have you kept your total continuous elapsed time per observation within the recommended max. observation times?
  


• Observing conditions requested (for queue-scheduled observations):
• Have you specified the most lenient observing condition constraints to achieve your science?  Changes to more lenient constraints is allowed, changes to stricter constraints requires Associate Director approval.
• Is the expected image quality (scaled to the airmass of your target) sufficient for your program?
• What level of cloud cover is acceptable? Is photometric weather required?
• Water vapor content is usually only relevant if you are observing in the thermal IR (3 to 5 microns).  For observations below 2.5um, has water vapor been set to ANY?
• Sky background is ignored for near-IR observations.
• Have you considered the true probability of execution, equal to the product of the probabilities of each of the conditions listed above? 
  
  
• Telescope peripheral wavefront sensors:
• Have you specified an appropriate guide star (just one) for the peripheral wavefront sensor(s) such that the PWFS probe arm(s) will not vignette the science field? (the GNIRS OIWFS is NOT available)
• Will the same guide star be accessible for all planned dither positions?  If not, has the PWFS been set to "freeze" in the alternativee positions, or have alternative guide stars been specified?
• Have you selected PWFS2 (recommended)?  

Last update Dec 14, 2004; Bernadette Rodgers and Greg Doppmann