GMOS Phase I (Proposal) and Phase II (OT) Checklists

To demonstrate technical feasibility or speed verification you should consider the following checklists when writing your telescope proposal or preparing your Phase II program.

• Phase I (proposal) checklist
• Phase II (Observing Tool) checklist

Checklist for GMOS Phase I proposals

• Instrument configuration:
• Is the filter (for imaging) and the filter, slit and grating (for spectroscopy) specified in the proposal instrument resource list?
• Is the grating you need available?
• Does your choice of slit and grating give appropriate spectral resolution and wavelength coverage?
• Telescope peripheral wavefront sensors:
• It is not recommended to use the peripheral wavefront sensors with GMOS. Have you made sure that an OIWFS guide star is selected?
• On-instrument wavefront sensor
• Have checked for vignetting caused by the OIWFS?
• Will your OIWFS guide star likely be accessible at all dither positions?
• Calibrations:
• Are the baseline calibrations sufficient? If not, what additional calibration data are required for your program?
• Is photometry better than 5% needed? If so, have appropriate photometric observations been included?
• Is absolute spectrophotometric calibration needed? If so, have appropriate spectroscopic standard star observations been included?
• Is accurate removal of telluric lines needed? If so, have telluric standard stars been inlcuded?
• Has sufficient observing time been requested for additional calibrations?
• Observing time:
• Did you confirm the exposure time and S/N using the GMOS Integration Time Calculator?
• Did you adjust the observing conditions specified for the GMOS Integration Time Calculator to match your requested conditions?
• Are overheads included in the time requested in your proposal?
• If you propose to use Nod-and-Shuffle on GMOS North, you need to add the additional overheads for Nod-and-Shuffle to the time requested.
• Have overheads been included for additional calibrations?
• If many very short exposures are needed, you may need to include larger overheads to account for the lower observing efficiency.
• If accurate centering of the slit on the target is essential, have appropriate overheads been included to allow periodic checks of the slit centering?
• Observing conditions requested (for queue-scheduled observations):
• Is the expected image quality (scaled to the airmass of your target) sufficient for your program? What is the minimum image quality necessary for the science?
• What level of cloud cover is acceptable? Is photometric weather required?
• Is dark time required?
• Note the product of the probabilities of each of the conditions listed above. You might wish to reconsider the minimum requirements of your program, and/or consider submitting your project as a queue-scheduled observation.
• Recheck the observing conditions requested!

Checklist for GMOS Phase II (OT) programs

1. Are guide stars selected for the GMOS OIWFS? The PWFSs are not used with GMOS. Can the guide stars be reached for the selected position angle? Are the guide stars within the magnitude limits for the OIWFS?
2. Have you considered spatial dithers for imaging? There are gaps between the three detectors in GMOS, see the description of the GMOS data format.
3. If imaging in the z-filter, have you considered how to handle the fringing? The GMOS-N detectors have significant fringing redwards of about 750nm. For imaging in the z-filter, the fringing is about +-2.5% of the sky background level. GMOS-S fringing is worse than the GMOS-N fringing.
4. Have you considered spatial dithers for spectroscopy in the red? The GMOS-N detectors have significant fringing redwards of about 750nm and for GMOS-S the fringing becomes apparent redward of about 700nm.
5. Have you considered spectral dithers for spectroscopy? There are gaps between the three detectors in GMOS, see the description of the GMOS data format. If complete wavelength coverage is essential, then two sets observations with slightly different wavelengths (~5nm shifts) are needed.
6. Are the integration times reasonable? Individual imaging observations should not be longer than 10-15min, individual spectroscopy observations should not be longer than 60min. Short exposures result in large overheads from the readout of the detectors, and may give data dominated by the read-noise.
7. GMOS observations that take more than about 4 hours to complete will be split. In such cases have you added a note explaining how many reacquisitions you have assumed for the calculation of the overheads?
8. Have you read the details about the overhead calculations? Taking the correct overheads into account, do your defined observations fit within the allocated observing time?
9. If your program is a MOS program, have you defined you pre-imaging for the first Phase II submission? You will get the chance to modify the MOS observations once you design your mask. However, the pointing and PA of your target cannot be changed between the pre-imaging and the MOS observations.
10. If you are using the IFU in two-slit mode, you will have to use one of the color filters to avoid overlap between the spectra.
11. If your observations include longslit spectroscopy with two or more targets observed simultaneously, you need to prepare finding charts. Such a finding chart should show both (all) objects on the same chart, and have a line indicating the location of the slit. Finding charts should be sent to your Gemini Contact Scientist (FITS with WCS, GIF or PostScript).
12. If your target for longslit or IFU spectroscopy is fainter than about R=18 you will need to prepare a finding chart.
13. If your program is a spectroscopy program, have you included the appropriate acquisition observations?
14. If your program is a spectroscopy program, have you included the appropriate baseline GCALflats and daytime calibrations?
15. If your program is a spectroscopy program, have you included the observation for the flux (spectral-response) standard?
16. If your program is a MOS program, have you included the appropriate mask image(s) and twilight flat field(s)?
17. When done, please double check all the observations in order to make sure your Phase II is ready for the next GMOS run.
18. If your program is a MOS program, prepare yourself for the mask design by reading the MOS instructions in detail and installing the required software.
19. Have all observation classes been set correctly?

Last update: June 15, 2005; Bryan Miller
Previous version: June 25, 2003; Inger Jørgensen