Sensitivity

For faint targets, GPI is expected to achieve 5-σ sensitivity at H=23 in one hour in spectroscopic mode. Achieved sensitivity is a function of many parameters, including contrast, inner working distance, brightness of the central star (if any), observing mode (dithered, sky-offset, sky-rotation) and it is not yet possible to provide estimates for all modes. Further details will be made available upon commissioning, but for the purposes of PIs generating proposals for Campaign observing, please assume that you will require a typical observation of at least 1 hour on each science target, irrespective of filter. If you believe that your programme will require significantly more or significantly less than this per target, please state so clearly in your proposal and contact the instrument scientist to confirm that the estimate is appropriate.

Overheads

The nominal GPI acquisition time is 10 minutes. This time is expected to apply to both coronagraphic and non-coronagraphic modes when the target is a bright (V <~11), single star, and should be added into your overall time estimate.  Fainter targets, or targets in very crowded fields requiring the use of finder charts, may require longer acquisitions.  Please note that the field of view is very small; so accurate positions and proper motions will be essential for efficient acquisitions. 

The following will be included as baseline calibrations (for baseline telluric standard frequency, see the IR Calibrations page). You do not need to account for these in your total requested time:

• PSF standards
• Telluric cancellation standards
• Polarization standards