Hokupa'a Observing

Observing with Hokupa'a and QUIRC is more complex than observing with a straight NIR imager due to (1) the subleties of observing with adaptive optics and (2) neither Hokupa'a nor QUIRC were designed to be Gemini facility instruments and as such there is only a minimal interface between the facility and instruments. In what follows the basic considerations while observing are outlined. Observers should consult the Hokupa'a/QUIRC operation manual in the Documents page.

For classical observing with Hokupa'a on Gemini the typical observing team consists of a Gemini System Support Associate (observatory operation), a Hokupa'a operator (from UH/IfA), and the visiting classical observer. On your first night of a classical observing run a support astronomer will also be on the summit with you. You are responsible for running the camera (QUIRC) and doing any data quality assessment.

On a typical night, the night will consist of evening calibrations, science observations (including acquiring, observing, sky/PSF calibrations), and morning calibrations. Upon arrival on the summit while the others set up the telescope and Hokupa'a you should start taking darks and flats. This typically takes 30-45 minutes but this will depend on your familiarity with the systems and what calibrations are needed. Target acquisition involves getting the Hokupa'a wavefront reference source (AO guide star) into the wavefront sensor, orienting the QUIRC field, and possibly acquiring a telescope guide star for tracking/windshake correction. For the most part this process will be transparent to you but you will need to specify for the Hokupa'a observer the dRA and dDec of the science field offsets from the AOGS. This process is explained in detail in the Hokupa'a/QUIRC operations manual in the Documents page. Note that the offsets are made in millimeters in the telescope focal plane using the conversion of 1.6"/mm. Offsets for dithering are specified from this initial offset position (also in mm). QUIRC camera operations are straight forward although no scripting is available. Calibration flats are done using dome flats, twilight flats or the facility calibration unit (GCAL). Note that the internal lamp brightnesses for GCAL precludes it use for J, K, Kprime, and H+Kprime. For these filters you must choose between twilight flats and/or dome flats.

Created 25 January 2001; Mark Chun