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JWST Cycle 1 Guaranteed Time Observations (GTO) proposals are submitted in three stages: initial proposals (Stage 1), finalized observation descriptions (Stage 2), and complete technical descriptions via the Astronomer's Proposal Tool (APT; Stage 3). 

 By NASA Policy, each JWST Guaranteed Time Observer (GTO) is required to submit a description of the proposed Cycle 1 science program, including specific targets and specific observations, seven months before the Cycle 1 GO Call for Proposals is released. Those submissions are reviewed by the STScI Director for potential duplications. The Cycle 1 science observations are required to be finalized at a date determined by the STScI Director that is at least 2 months before the Cycle 1 GO Call is released. The GTO Cycle 1 observation descriptions will be made public at that time. Once the observation descriptions are finalized, detailed technical observing proposals are required to be submitted using the Astronomer’s Proposal Tool. This document describes the processes through which those Cycle 1 submissions are made to STScI, the process for subsequent cycles and the opportunities for making changes to GTO science programs, in accordance with the policies specified in NASA-SMD Policies and Guidelines for the Operations of the James Webb Space Telescope at the Space Telescope Science Institute.The total time (including overheads) requested for all JWST GTO programs must be between 25% and 49% of the total time available for all GTO and GO observing proposals in Cycle 1 (NASA-SMD Policy 9).


Stage 1: Initial GTO Proposal Submission

The JWST GTOs must submit proposals describing the full science program to be undertaken in Cycle 1, no later than April 1, 2017. Submissions must be coordinated as follows,

  • The NIRCam PI will submit a single proposal covering the full range of science to be undertaken by all members of the NIRCam team;
  • The NIRSpec Team will submit a single proposal covering the full range of science to be undertaken by all members of the team;
  • The U.S. MIRI Science Lead, and each of the eight U.S. MIRI Science Team members will submit a proposal, for a total of nine proposals;
  • The European MIRI Science Team will submit a single proposal covering the full range of science to be undertaken by all members of the team;
  • The FGS/NIRISS PI will submit a single proposal covering the full range of science to be undertaken by all members of the team;
  • The U.S. Telescope Scientist, and each of the six interdisciplinary scientists will submit a proposal specifying the full set of planned science observations for a total of seven proposals.
The proposal consist of two parts: a narrative document detailing the science investigations included in the proposal; and appropriate forms that specify the observations to be executed.  Templates for each are provided below . There will no page limits for each proposal. 

The narrative document specifies the PI by name, the description of the PI position (e.g., MIRI US Team Lead, Telescope Scientist, etc.) and the total wall-clock time to be charged against the PI's GTO time allocation. The document has the following sections:

Science summary: This section must be used to provide a short (typically 1 paragraph) description of each separate science investigation that will be undertaken within the Cycle 1 program. GTOs must identify investigations where the time will be shared between different GTO teams and specify how the time will be divided. This section will be published as an explanatory supplement with the list of science observations to provide the community with a summary of the range of science being undertaken by the GTOs.

Scientific justification for coordinated parallel observations (if appropriate): Coordinated parallel observations should have science goals that support or complement the prime science program. GTOs requesting such observations must provide a scientific justification. This should clearly indicate the role played by the parallel observations and whether they are essential for the interpretation of the primary observations or to the science program as a whole, or whether they address partly or unrelated issues. The justification will be assessed by an independent review panel that will make a recommendation to the STScI Director regarding their implementation. If the coordinated parallels are not implemented, the prime observations will be available for pure parallel observations. This section will not be made public.

Detailed description of triggering conditions for Target of Opportunity Observations (if appropriate): GTOs must provide clear definition of the specific criteria that would lead to triggering ToO observations of a particular target or phenomenon. Those criteria will be assessed by an independent review panel that will make a recommendation to the STScI Director regarding their clarity. GTOs may be requested to refine the trigger criteria should those criteria be deemed insufficiently precise. This section will not be made public.                               

Submissions using the JWST Astronomer’s Proposal Tool (APT) are not required at this time. However, proposers should use the current version of APT (nominally APT 25.0), which includes an up-to-date calculation of overheads, in this stage of their observation planning. 

The observation specifications must include the full list of proposed Cycle 1 observations, including each target, a description of the mode of observation, the expected integration time on each source and the associated overheads as given by APT 25.0, in accordance with the information requested in the instrument observation templates linked below. The proposal text will also include a scientific justification for any proposed coordinated parallel observations, and a clear description of the trigger criteria for any ToOs. Both of these sections will be subject to review by a committee of scientists selected by the STScI Director. In the case of collaborative programs between GTOs, the proposers must give a clear indication of how the total time should be divided among the PIs. Observation list templates are provided below.

Note that charged durations (including overheads) derived in developing observation specifications using versions of APT prior to 25.2 (scheduled for release June 1, 2016) will be preliminary estimates, sufficient only for planning and Stage 1 preparation. APT versions 25.2 and beyond will contain the sanctioned overheads and charge durations necessary to finalizing observation specifications, including for GTO observations, as detailed in Stage 3 below.

GTO Stage 1 Proposal and Observation Description Templates

Teams should complete the GTO Observation Specification Workbook [.xlsx] to provide descriptions of their observations for Cycle 1. The Guide to the Observation Specification Worksheet [.docx] gives brief details on the fields in each worksheet of the workbook. A GTO Proposal [.docx] should accompany the workbook, to provide general science summaries, coordinated parallel justifications (if applicable), and the breakdown of total hours to charge which programs. If you prefer, you may use this alternative total time charge table [.xlsx], provided by Pierre Ferruit.

 The proposal abstracts will be made public in the stage 2 release of the observation specifications.

Stage 2: Finalized GTO Observation Descriptions

JWST GTO observation specifications for Cycle 1 will be made public after any duplications between GTO proposals are resolved, and they are verified to be within the allocations specified by NASA policy. This process will be completed no later than June 15, 2017. The GTO observation descriptions will be published at that time, and protected from scientifically unjustified duplications in subsequent Cycle 1 Early Release Science (ERS) or General Observers (GO) observing programs.


Stage 3: GTO APT Program Submission

In early June, STScI will issue Build 14.1 of Proposal Processing System, including an updated version of the Astronomer’s Proposal Tool (APT). GTOs must use this version of APT (nominally APT 25.2) to define the observing programs planned for execution in Cycle 1. Overhead parameters will be frozen in this version, and used in all versions of APT used to develop proposals (including those for the GO) in Cycle 1.

The GTO teams should begin their formal APT submissions (in APT 25.2) for technical review and revision on July 28, 2017.  The APT reviews and revisions are likely to be an iterative process, which must be complete by September 15, 2017. The final APT files will be made publicly available on December 15, 2017. The GTO schedule in context with the full JWST Cycle 1 proposal schedule is as follows: 

Based on recommendations made by the JWST Standing Review Board, NASA is re-scheduling JWST’s launch window for 2021. Given those circumstances, STScI will delay the Cycle 1 GO/AR proposal deadline until no earlier than February 1, 2020

A revised proposal schedule will be developed in consultation with the JWST Users Committee, the JWST Project and representatives from the European and Canadian Space Agencies. Proposals already submitted in response to the Cycle 1 Call will not be carried over and will need to be resubmitted.

The APT proposals must specify detailed observations for each science target included in the science programs. Individual members of GTO teams may each submit multiple Cycle 1 GTO APT proposals. STScI will ensure that each APT is grouped with the appropriate GTO allocation. For example, the NIRCam PI may subdivide the Cycle 1 observing program by science topic, with different team members as PIs on individual proposals; in that case, the total time charged to the NIRCam PI will be the sum of the total time (including overheads) requested by the validated NIRCam-team APT proposals. The Cycle 1 GTO APT files will be publicly accessible.