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Directors Discretionary Time Process

A fraction of the observing time on both Gemini North and South telescopes may be used for Director's Discretionary Time (DDT) proposals, which any astronomer worlwide can submit.

DDT proposals must belong to one of the following categories:

  • Proposals for observing targets requiring immediate or timely observation of a sudden or unexpected astronomical event. Note that proposals for Target of Opportunity observations, i.e. targets that cannot be specified in advance but which have a well-defined scientific aim and an external trigger, should be made via the normal proposal process. This is considered to be the case for e.g. SNe, GRBs, and other classes of targets found as part of surveys or monitoring. However, DDT proposals may request ToO status if the science goal of the proposal justifies this.
  • Proposals requesting observations related to a highly competitive topic.
  • Proposals requiring follow-up observations of research conducted on other space or ground-based facilities, where break-through results are expected from a timely follow-up.
  • Proposals of a risky nature requesting a small amount of observing time to test the feasibility of a technique or of a program.

Proposers should provide a very clear and concise scientific justification. They should also describe their strategy for data reduction and fast publication of the results in a high-impact refereed journal. Normal allocations are up to 4 hours; longer requests can be accepted provided the scientific case warrants the time.  DDT Proposals are judged on the following criteria:

  • Uniqueness: must not duplicate current queue projects
  • Chance of yielding a high-impact result
  • Level of reward, if a "speculative" proposal
  • Urgency (must be clearly not possible via the regular proposal cycle)
  • Ability of team to make quick use of the data
  • Feasibility, given the current queue.

DDT proposals may be submitted at any time using the Gemini Phase I Tool for the current semester (ie. all DDT proposals for semester 2015A must be submitted using the 2015A PIT). The Phase I Tool installation files are available here. Submit by choosing "Director's Time" from the Proposal Type menu in the Time Requests tab, entering the time requested, and then clicking "Submit this Proposal" in the Submit tab. Only proposals submitted this way will be seen and reviewed by the relevant staff (the Gemini Directors and Heads of Science Operations). Technical assessments will be done by Gemini staff where necessary. Projects are generally placed in Band 1, but Band 2 may be used in some circumstances. PIs do not need to request one or other band. Once validated, approved and ranked, proposals will be prepared using the Phase II (Observing) Tool to be included and activated in the Observing Data Base (ODB) for their execution in the queue. Please note that within one month following the observations, the PIs of executed DDT programs must submit a report on the achieved science,and on the status of the publication process, to the Deputy Director, Associate Director for Science Operations, and the relevant Head of Science Operations.