Change page style: 

Classical Mode

An investigator may request that his/her program be classically scheduled on submission of their Phase 1 proposal. If accepted by the TAC, the program is assigned specific nights on the telescope; usually whole nights are scheduled and the minimum allocation is one night. Individual partner countries may run mini-service "classical" observing programs that aggregate smaller proposals together. Specific scheduling restrictions (preferred dates, impossible dates, synchronous observations with another facility) may be requested by investigators as part of the Phase I proposal.

Proposals for classical time must specify the minimum acceptable observing conditions . If these observing conditions constraints are restrictive, a backup program must be described which can use poorer conditions. During a classical observing run, if conditions are worse than those required by the main or alternate classical program, the time will be used for queue observations. In this case, the classical time will not be re-scheduled, but the partner responsible for the classical program is not charged for time spent executing the queue. Note that starting in 2009A, Rapid Targets of Opportunity can interrupt classical-mode nights (excluding Subaru and Keck exchange nights), unless the classical observation is time-critical. Time will be reimbursed to the interrupted program during queue time with similar conditions as the interrupted time.

Classical programs are not reimbursed for weather or technical losses. Classical scheduling is not appropriate for programs requiring rarely occurring conditions such as the best image quality, or the dry and photometric conditions often required for mid-infrared observations. It is also not appropriate for a programs with targets widely distributed across the sky (and thus not accessible during the full night). In these cases programs should be queue scheduled.

Technical support for investigators is provided by the partner National Gemini Offices (NGOs). For successful classical proposals, the detailed definition of observations is undertaken in Phase II of the proposal process using the Observing Tool (OT) just as for queue observations. The Phase II deadline is the same for both queue and classical programs, and is typically a month after notification of the award of time.

We strongly encourage the classical observer to meet with the observer support scientist (contact scientist or IPOC) assigned to the program. This is important for new and seasoned observers alike since procedures are constantly improved. Classical observers interested in familiarizing themselves with observing procedures ahead of their run are encouraged to contact the local Head of Science Operations in advance. It is often possible to accommodate visiting PIs during normal nighttime operations the night before their run, either at the telescope itself or over a video link from the base facility.

A Gemini observer will be available at the summit during the first night of the run to provide support for the observation. If the classical run extends for more than one night, then a Gemini observer will be available on-call for the rest of the allocated nights. The SOS (Science Operational Specialist) member will contact the on-call Gemini observer if needed by the PI.

Basic Guidelines for Classical Observations

We remind the observer that the SOS is the safety duty officer at night. As such, the SOS has the final say about the safety of people and telescope. This person will decide, for instance, if the telescope needs to be closed due to the weather conditions.

A minimum of one and a maximum of two visiting astronomers may participate in the observing run. At least one visiting astronomer must be present at the summit. Instructions and travel information for visitiors to Gemini North and Gemini South are available. Classical observers must also complete the forms linked to from these visitor pages 4 weeks prior to their first night.

Modification of approved classical programs follow the same procedures as for queue programs and must be made via the change request process. Changes requested less than 7 days ahead of the run will be processed on a best-effort basis. If the PI expects changes to be requested during the run, prior notification to the local Head of Science Operations will make it possible for the staff support to process these requests in real time.

Finally, we remind the observers that their data will be available for you to analyze and download from the CADC archive minutes after you take the data. You will need an account with CADC before been able to access your data. So we encourage you to do so as soon as possible. Please note that this account has a password that is different from your Gemini PI password.

Rules for GMOS MOS Classical Runs

  • If GMOS pre-imaging is required to generate the object and mask definition files, pre-imaging will be done in queue mode prior to the classical run.
  • Mask designs must be submitted at least 4 weeks before the run.
  • No masks will be cut once the observing run has begun.
  • The masks are mounted on mask metal frames that are installed on the instrument. The instrument has a limited number of slots (10) available for mask frames. So special care is needed when planning for the run.
  • If the run consists on more than one night, then a list of masks to be observed must be sent to the QC before 9:00am on the day that they will be observed. If not, then we assume that no mask changes are needed and none will be made.
  • During a run, we advice the observers not to request that a recently observed mask gets reinstalled on the instrument.
  • In general, we do not reuse masks from previous semesters. So masks observed on previous semesters will have to be re-cut before they can be re-observed.