Targets
Target tables are specially formatted tables available through the Web form ("Enter Tables" button) and/or through the LaTeX template. These tables are required for all Gemini runs, and for any queue or service runs on other telescopes
The format of the target tables is the same for all telescopes/instruments except for Gemini which has its own requirements and specifications. The remaining sections of this document deal with these target tables explicitely.
The fields in the non-Gemini target tables include:
Object ID queue: specify a unique 3-digit number for each target Object 20 characters maximum RA e.g., xx:xx:xx.x DEC e.g., +-xx:xx:xx.x Epoch e.g., 1950.3 Magnitude Filter Exposure time in seconds PER EXPOSURE Number of exposures Days from new moon use a number 0-14 Sky condition use "spec" or "phot" Seeing max allowable PSF FWHM (arcsecs) Comment 20 characters maximumThe fields in the Gemini target tables include:
Object ID unique 4-digit number assigned automatically Object 20 characters maximum RA e.g., xx:xx:xx.x DEC e.g., +-xx:xx:xx.x Epoch all targets must be B1950 or J2000 Magnitude Observation time total exposure time and overhead in minutes for all filters Image quality these next 4 parameters are given as percentages as described at Cloud cover http://www.us-gemini.noao.edu/sciops/ObsProcess/obsConstraints/obsConstraints.html Water vapor Sky background Guidestars P=PWFS, 0=OIWFS, A=AOWFS, lower case=marginal selection (no longer found in phase I) Comment 20 characters maximum
Each target table generated through the Web form is restricted to 50 targets, but each run can have multiple target tables.
Targets can be typed directly into the target table or a list of targets can be uploaded through the Web form using an ASCII-formatted file. The uploaded file contains the target name (20 characters max.), epoch (only B1950 or J2000 allowed for Gemini), and the RA and DEC (+-xx:xx:xx.x) in a tab-separated list. For example:
NGC 4151 B1950 12:08:01.1 39:41:02 NGC 7027 B1950 21:05:09 42:02:03 L183 B1950 15:51:35.7 -02:40:54Once the targets have been uploaded into the target table the user can edit the table entering the remaining required information.
For Gemini, the observing time should be the total wall-clock time (in minutes) needed to observe your target. This must include the sum of all exposure times in all filters plus overhead. Do not simply enter the time returned from an exposure time calculator as this will not include overhead for target and guide star acquisition, which will typically be an additional 15-30 minutes per pointing. Offsetting for sky exposures and dithering will also add to the total observation time. In most cases, summing the observation times for all targets should very nearly equal the total time request from the front page of your proposal. It can be very helpful to reviewers if you include a specific breakdown of your time request in the body of your technical description.
The Gemini Observatory website provides information on the performance of these instruments which can be used to estimate integration times and overhead. This can be found in the "Performance and Use" sections of their web documentation.
Gemini maintains Integration Time Calculators for its facility instruments at
For details on the specific
conditions associated with percentiles for each condition,
see the Gemini observatory web page at
Gemini observing condition constraints
The minimal acceptable constraints on observing conditions
(image quality, sky brightness, water vapor, and cloud cover)
must be specified for Gemini targets. These constraints are
specified according to the percentile of time the conditions
are matched or exceeded. So, selecting "20" indicates that you need
conditions for that constraint that occur only 20% of the time.
If you also select "20" for another non-correlated constraint, you would
essentially be requesting conditions that occur just 4% (20% x 20%)
of the time (assuming the other constraints are set to "any").
To optimize the chance that your program can be carried out, select the
most generous limits you can for your observations.